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Who are some of the Koha-Ace characters in the ED?
During the ED of the Carnival Phantasm Special Season OVA, we see just about all of the cast from major Type-Moon works as Koha-Ace characters.
From right to left, who are the person (13th from the left, not including the floating characters) between Hisui and Miyako, the person (10th from the left, not including Keitai-san, the cellphone) between Caster (Fate/Extra) and Chikagi, and the very last person on the far left (first one from the left)?

I believe the one on the far left is Kariya Matou from Fate/Zero,

the one next to Chikagi is Rani VIII from Fate/Extra (it's a bit hard to see as reface is mostly obscure, but the clothing and skin color matches),

and the one in front of Miyako is Assassin (Li Shuwen), also from Fate/Extra (the wardrobe practically gives it away).

getting all their name would also be helpful..


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Why do anime/manga characters have big eyes?
Going as far back as Astroboy, anime and manga characters have had big eyes.
What is basis of this trend? How and where did this originate?

Anime characters having large eyes is generally attributed to Osamu Tezuka{1}, an artist prolific enough to be called the "father of manga", and the creator of Astro Boy, the source of the image you shared in your question (among other manga).
At the time of Astro Boy (1952), Tezuka was inspired by precursors in animation, largely those of Walt Disney, but including others as well, before adapting them to a more Japanese stylization. Two such characters who served as inspiration were Mickey Mouse and Betty Boop:

It is from Astro Boy and Tezuka's other works that a lot of modern manga and anime style evolved, and the big eyes are one of the things that stuck around. Fred Ladd, the man responsible for bringing Astro Boy to the United States, corroborates this, saying that Betty Boop was indeed one of Tezuka's favorite characters. The "runaway" success of Astro Boy was what led other studios to imitate Tezuka's style.{2}
It is also the case that the large eyes tend to look "cuter", much like they were intended to on characters like Mickey Mouse and Bambi. This continues in anime and manga; younger characters tend to have the largest, "cutest" eyes, while older characters generally have smaller (and often sharper) eyes, which can be seen in this image containing Hunter x Hunter characters:

So, while the style Tezuka used—which has carried on in new anime and manga media ever since—was largely based on Western animation style, the eyes can still serve as a good way to indicate personality or the feel of the character that the viewer is supposed to have.
Sources and other Links

Wikipedia sources this to "Watching Anime, Reading Manga: 25 Years of Essays and Reviews".
MIT Anime Resources: Big Eyes (2008-07-23)
TVTropes on Anime (a very brief mention)
Wikipedia on anime eye styles

Great comment. I want to add that comparing to traditional european and american comic, japanese mangas are more subjective in style, giving more importance to character's emotions than to their position and other objective information. The eyes are the mirror of the soul, so manga characters have big eyes that help to better communicate those emotions. Scott McCloud's "Making Comics" treats this subject.

There's plenty that doesn't.
The facial features and eye shapes are what makes anime its distinct style. Look at Osamu's art style then contrast it with Gundam, most Jump Comics franchises, Studio Ghibli style, and another early anime, Lupin the 3rd and then try to make the case that Disney/Tezuka had any influence on anime's visual style.
Especially different from Tezuka and Disney's style are other relatively small eyed anime like Hokuto no Ken, JoJo, Berserk, and lots of other adult-targeted anime.
And I forget what book it is, but there is one where the introduction on the first page is a summary by Katsuhiro Otomo explicitly stating, among other things, that the anime style is not the same thing as the kind Osamu Tezuka drew. He just innovated storytelling and animation techniques within anime and the idea of using big eyes to more clearly express emotions.
Big eyes themselves were an idea Japan was already very familiar with anyway. Here are some direct contrast just to further cement the point

Pluto (Naoki Urasawa) vs Astro Boy (Osamu Tezuka)

Kingdom Hearts
There are at least as many animes without big eyes as there are with big eyes. Anime is not by default the "big eyes" look that a surprising number of people ignorantly believe it to be, and obviously, has absolutely no resemblance to any Tezuka/Disney style.

source: Stack Exchange

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How does the summoning of the Ten Tails work?
If Demonic Statue of the Outer Path requires only a part of the chakra of the Nine-tails and the Eight tails, why did they have to kill the other Jinchuuriki to obtain the tailed beast just to complete the Juubi?
Why not obtain only parts of the chakra of each tailed beasts?

Because the Juubi will not be revive in its full form and make the juubi weaker for every tailed beasts that has been extracted only by parts.

Having the chakra of kyuubi and hachibi will suffice, but the Juubi is considerably weaker. Having the full kyuubi and hachibi will essentially create the juubi in its perfect form. For each bijuu that juubi doesn't have, the monster gets weakened.
It's basically like comparing a fraction of the kyuubi's chakra vs an entire kyuubi with his full chakra at your service. The amount of power is significant.

Ah reference might be helpful though.

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What is Naruto's age?
I'm sort of new to Naruto. I just finished most of part one and about to start Shippuden. I was wondering how old was he at the start of Shippuden? I'd really like to know as I have researched it a bit and can't figure it out. Maybe it slipped by me.
There's been all sort of answers online, but no definitive evidence. Evidence would be nice.

From the wiki under Personal

Part I: 12 - 13
Part II (Shippuden): 15 - 16

It is also worth noting that when Minato asked him his age after stoping naruto from releasing the Kyuubi's seal, Naruto told him that he was 16.
On the wiki, it also says that he graduated from the Academy at age 12, some time passed and we know he spent ~2.5 years away training with Jiraiya so accounting for any time that may have passed, it eventually adds up.

Oh I missed that. I can't believe he's that young and so powerful.

When Minato asked when he was about to release the Kyuubi's seal, Naruto answered that he was 16.

I don't think I'm that far yet but I'll keep a look out for that.

Naruto is 17 years old at the time of writing. But if you think that's young, Itachi was only 17 years old in the first part of Naruto.

 Meaning he was 20-22 when Sasuke killed him.

Not to mention he was 13-14 when he killed his entire clan... So yeah, the mangaka has a really good opinion of young people xD

Can you give a chapter or come chapters as frame of reference?


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Is the Fruit of Grisaia an actual fruit?
Having played a fair bit of -LE FRUIT DE LA GRISAIA- (Grisaia no Kajitsu, literally "The Fruit of Grisaia"), I have to admit that the title has confused me more than anything else. It seems to have very little to do with the plot of the VN, at least so far.
What is the meaning of the title? Is it titled after an actual fruit, and if so what is the fruit? Also, what significance does it have to the plot?

Considering that the subtitle for it is in French, I'm making a logic jump by guessing "grisaia" is just a conjugation/grammatical form of the word "grisait" or something close (I don't know french at all, but then again it could be a classic case of the Japanese tripping up with a foreign language).
According to google, grisait means something between "intoxicate" and "fascinate" in french, so I guess the VN's title was going for "The Fruit of Intoxication"? Sounds fairly plausible at least...

The il/elle indicative imperfect tense conjugation of the verb "griser" is "grisait," but since it's a verb, it doesn't make sense for it to be used as a noun in the title.

According to this interview with Front Wing Producer, President, and CEO, Ryuuichirou Yamakawa:

山川　絵画の画法でモノトーンで書く手法を「グリザイユ」というのですが、これを少し、いじって『グリザイアの果実』つまり「灰色の果実」という意味が込められています

The word "grisaia" is a corruption of the French term used in art, "grisaille," a method of painting in monochrome or near-monochrome, typically to resemble the appearance of marble sculptures. So literally it's meant to be "the gray-colored fruit" or something like that.
The fruits refer "guilt" the heroines bear, as described by the story synopsis of the game:

──その学園は、少女達の果樹園だった。
  外敵から隔離された学園にやってきたのは、生きる目的をなくした一人の少年。
  守るべき物を見失い、後悔と贖罪のみに費やされる人生の中で、その少年に残されたのは首に繋がれた太い鎖と、野良犬にも劣る安い命。
  そして少年は、その学園で少女達と出会い、新たな希望を見つけ出す。
──その少女は、生まれてきたことが既に間違いだった
  逆らった罪──
  ──生きながらの死
  誰も守ってなんかくれない──
  ──そして生き残った罰。
そこは、少女達の果樹園。
  彼女達は、後悔の樹に実った懺悔の果実。そんな少女達に、俺はいったい何が出来る…？
  それは、一人の少年が夢見た永遠の希望──
That academy – used to be the orchard of young girls.
  A lonely boy, who lost his purpose to live, came to that isolated-from-the-foreign-enemies academy.
  Lose sight of things that should be protected, he spends his life in living day by day with regret and atonement. His life is cheaper than a stray dog when that heavy cangue still around his neck.
  And then at that academy, the boy finds out his new hope in encountering with these girls.
──That girl, who being born was already a mistake.
  Who defied the sin──
  ──Who died though she’s living.
  Who no one will protect── [Note: translation corrected]
  ──and who being punished for surviving.
That place is the girls’ orchard.
  The trees of regret bear the fruit of repentance of those girls. What on earth can I do for these girls...?
  That is the eternal hope which the lonely boy dreamt...

Each heroine is represented by a fruit:

Yumiko = grape
Suou = cherry
Michiru = lemon
Irisu = strawberry
Sachi = apple

Grisaia is a bastardization of the French term Grisaille which refers a method of painting in monochrome. Grisaille in Japanese is グリザイユ or gurizaiyu and the only difference in Japanese between Grisaia (グリザイア) and Grisaille is the last sound (yu in grisaille and a in grisaia). The reason for the name and why the end is changed won't really come up until the third and last game in the series though.


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What is the power of the seventh Witch?
What exactly is her power?
Why did Miyamura's sister, Yamada, and the president not get affected by her memory erase?
I understand that perhaps she couldn't erase Yamada's memories, but then how did the other evade the memory erase?

The 7th witches power is the the power to forget everything about the witches.
Miyamura's Sister ran away from her and escaped so was not affected. She's hasn't returned to the school since.
Yamada's power reversed the power and everyone else forgot about him and the witches.
The president was not affected because the student council president is the only student who may be immune to the witches' powers.
There's some fan speculation that the presidents are people who have Yamada's power, or have had.

I'll try find the exact scene where it mentions the student council president later, but I'm in work atm ^^

I guess I should also ask what exactly did the 7th witch do? If she didn't kiss Yamada, how did her powers activate? Also I found the part where the Prez tells Yamada it is just an "iron-clad law" that only the president may know of the 7 witches.

I'm starting to get more curious about this absolute law where the only person that can know all 7 witches is the president. If both Tamaki and Yamada learned about the 7th witch from Miya's Sister, then how did the witch know that they knew? Even the president doesn't have this knowledge, which is why he asked Yamada.

oh yeah, I forgot that she didn't actually kiss him. I have a feeling that the plot point might be revealed once Yamada retrieves the second book detailing the witches.
I'd say the 7th witch probably heard all the huckus that Yamada was making around the school, and found out that way. I have no solid evidence for that though

This answer is no longer accurate. The power of the 7th witch is to make everyone, except for her target, forget everything about the witches.

@nhahtdh - I haven't been keeping up with the series - feel free to edit your stuff in or put a new updated answer

The 7th witch's power is memory manipulation. She/he also has the power to see the witches out of the students in the school. This power was revealed on the second witch war arc when Yamada became the seventh witch.


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Which volume of novel or chapter of manga should I read next in Chrome Shelled Regios?
I finished watching Chrome Shelled Regios a while ago. I'm  now planning to read the light novel or manga. Having watched the anime, which volume (of the light novel) or chapter (of the manga) should I start at?

I believe The anime ends at about vol. 7, chapter 2 of the light novel.

As Krazer notes in his comment, the anime adapts the novel up to volume 7, chapter 2. So you should start from chapter 3. There are 24 volumes in all.


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What are the governmental structures of the countries in FMA?
The countries in FMA all seem to have different governmental structures. Amestris seems to be militarily run but I thought I saw references to some sort of Parliament. Xing seemed to have tribes but Ling is also the Prince. Ishval seemed to have some sort of set of elders, though I wasn't sure about that. What are the technical governmental structures of the three countries?

Short answer: Amestris is a military state which has a parliamentary republic form of government. Xing is a monarchy which has a clan structure beneath the monarch (emperor). Ishval, when it was a country of its own, had an unknown government structure but was probably split into communes; it is now under Amestris's government.

There is a long answer, too, of course...
Amestris

Amestris is a Unitary State, with a population of about 50 million and a Parliamentary Republic type of Government. The Head of State is the Commander-in-Chief of the Military who holds the title of "Führer" (大総統, Daisōtō in Japanese, a form of "Generalissimo") and who concentrates the ranks of Head of State and Head of Government. — Amestris, Fullmetal Alchemist Wiki

Amestris is a military state ruled by Führer King Bradley. As mentioned above, it is a unitary state (one in which there is one central government which decides what smaller branches handle) with a parliamentary republic government. So, yes; there is a parliament, but it is more-or-less just a cover for the central military control body that we see running the country for the entirety of the show.
It is mentioned that Amestris did not used to be a military state; it is not mentioned what type of government it had prior to becoming one.
Ishval
Ishval is implied to have once been a country, but is no longer a sovereign nation. Following the fall of Xerxes, many countries were assimilated into what is seen as Amestris in 1914 and onward. There is no given record of the government in Ishval at the time, though it is implied that it was a tribal land, not so much run by a government, but more likely small communes that worked on their own and were united by connections between them.
The man pictured below is a high-ranking monk, and who is most likely important in uniting the Ishval community (even prior to the War of Extermination).

Xing

Xing is a Monarchy, whose monarch holds the title of Emperor. It's composed by fifty hereditary clans all under the rule of a single Emperor, who cements his rule by taking the daughter of each clan's chief to be his concubine and bear him a single heir for each clan. — Xing, Fullmetal Alchemist Wiki

The country of Xing is, as stated above, a monarchy ruled by an emperor (part of which makes it an empire). Beneath the (unnamed) emperor are approximately fifty clans, most of which have an heir (about forty-three have heirs, the others do not). Two of the clans we are briefly told about are the Yao and Chang clans.

When Ling says he is a prince, this is basically a technicality; he is the leader of the Yao clan and an heir to the emperor's throne (the twelfth heir, I think). He has no special privileges above being the leader of his clan, so his rank as "prince" solely has to do with his position as heir.
Others
Drachma, the large and arctic country to the north, is not told to have any specific kind of government. However, given how it is the largest country around and is an arctic country, as well as the types of wars it fights, it is implied that it is an equivalent of Russia. Russia was, at the time, the Russian Empire, which I believe was also ruled by an emperor or tsar. Further reading: (Russian Empire: Government and administration, Wikipedia)
Creta, to the southwest, is a smaller country which is composed of tribes in a federation-like manner. (Further reading: Creta, Fullmetal Alchemist Wiki)


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What happened to Dana and the 15th Armored Battalion?
The start of Robotech: The Next Generation explains what happened when the Invid invaded. The Army of the Southern Cross was apparently wiped out, but was Dana Sterling and the 15th Armored Battalion also wiped out?

Dana appears in the comics Robotech: Love and War and Robotech: Prelude to the Shadow Chronicles so it would seem that she survived the destruction of the 15th Armored Battalion and may have continued the war against the Invid in some capacity, but after that her fate in unknown.

Now, there is a recently new movie called Robotech: Love Live Alive (2013) (adaptation of Mospeada Love Live Alive (1983) with some new animation) where you see Dana from the 15th squadron leaving Earth.
https://www.youtube.com/watch?v=W9txrDGHWnc
Dana heading to a Garfish spaceship to leave Earth.

In the movie Robotech The Shadow Chronicles it's confirmed they actually left with no problems because Louie from the 15th squadron is a secondary character.


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What does it mean that Gluttony is a fake Gate of Truth?
Gluttony is said to be a fake Gate of Truth, as shown by when he swallows Ed and Ling. They are transported to a place that is full of blood, which seems to be entirely different from the place where the real Gate of Truth takes someone. What does him being a fake Gate of Truth mean, as opposed to just being some sort of transportation device? What is the difference between his Gate of Truth and the real one?

Gluttony was created for the sole purpose of being a portal of Truth. Father was attempting to create a way to access the so-called "non-reality" (beyond the Gate) without paying a toll; essentially, he wanted to entirely bypass Truth so that he could access all alchemical knowledge within the Gate.

However, Father is not omnipotent; he was unable to create a portal which was able to do what he hoped for. Instead, what you see of Gluttony was the result: A portal, attached to a homunculus, that serves as a gateway to a different world, one that is neither reality nor non-reality (that is, it is somewhere between the universe and the realm of Truth).

It probably goes without saying at this point that the difference between this Gate and the real one is that, well, this one is useless. Basically, it's just its own dimension that serves as nothing but a place for Gluttony's consumptions to go. It contains no alchemical knowledge, no God (which would be in the real Gate), and no way out.


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Does Drachma play any role in FMA beyond being what Briggs defended against?
In the parts of FMA when they are at Fort Briggs, they say that Fort Briggs defends against the country of Drachma. As far as I remember, though, that is the only time that Drachma is mentioned. Is it relevant to any other parts of the series, or is it only important as a reason for Fort Briggs to exist?

Are you referring to Fullmetal Alchemist (2003)? or Fullmetal Alchemist: Brotherhood?

FMA: Brotherhood.

In that case I don't think there's a particular reason other than being that scary huge nation to the north to defend against. But I might be wrong.

Is it different in FMA (2003)?

Don't know, I haven't watched FMA (2003) to the end of it (not even to the middle of it :D)

In-universe, Fort Briggs exists because of Drachma; they are the only line of defense keeping the Drachmans from breaking the non-aggression pact.
Out-of-universe, it's the exact opposite: Drachma was added so that Fort Briggs had a reason to exist and to house one the toughest army around. Considering the allusion to Russia (Drachma shares many similarities), it is likely that it was to be seen as a powerful force. In order to have a powerful Amestrian army which was still isolated from Central, they had to be given their power from an outside, independent source: Drachma.

Drachma does play a further role, though. Starting at the end of episode 42 (Brotherhood), they launch an attack against Fort Briggs.

 Kimblee, doing what he does best, leads the Drachman army into a trap, claiming that Fort Briggs is weakened by the absence of General Armstrong and that he has men inside who will bring down the army from within.  The latter is a lie and the former is not a weakness, and Kimblee knows this; Kimblee, assisting Father indirectly, is creating a blood seal as one of the main components of the Nationwide Transmutation Circle. In this way, Drachma is necessary; the soldiers that die here are crucial for creating the blood seal, just as they were in the other major wartime conflicts that Falman explains to Ed.

Aside from justifying the Briggs fortress and army, and creating this wartime conflict, Drachma has no direct role in the events of Fullmetal Alchemist.

well drachma is said to be the largest country in FMAB (Bigger than xing if you extended the map.) The only way they would have expanded so far is if they had a strong military. The Non aggression pact wouldn't exist if father felt they were no match for Amestris. BUT, it since father is the true leader of Amestris he must have felt Drachma would have been a threat to the Amestrian military. so it can be believed they are one of if not the strongest nation in the FMAB Universe. However no the only major part they play in the Anime or manga was to forge the blood crest in the north.

From what I see, this answer only speculates about the strength of Drachma, without contributing to the question Is [Drachma] relevant to any other parts of the series, or is it only important as a reason for Fort Briggs to exist?


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Who was the child of the first Hokage?
We all knew that Tsunade is the granddaughter of the First Hokage, but who are her parents? What are their whereabouts?
The wiki said that "Despite the seal's strength, it almost broke at some later point when she (Mito Uzumaki) was going through childbirth."
Who is this child?

I don't think anything as such have been mentioned in the manga.

The name was never mentioned, nor it was ever discussed about Tsunade's parents or origins, other than she being the granddaughter of the First.
In short, we don't know. It's also likely to not be revealed anytime soon, unless the author would include it in a databook or something similar.


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Is this image from an anime or manga?

Is this image from an anime or manga? Which one is it from? I found it from a banner of an anime website.

That looks like "Naoto Fuyumine" from Dogs, which has a manga and anime.

Yup, the original image verifies this (some content may be NSFW): http://www.zerochan.net/1382405#full

@Eric If you're going to link to the original image, surely the copy on the artist's Pixiv page is a more reliable source. Anyway this confirms that the image is by the original manga author and was released at C83 in an artbook.

@LoganM My bad, Pixiv takes forever to load for me, so I avoid it whenever possible.

Oh wow, I thought that was definitely just some fan-art.


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Why is Pride's name different from the word "pride"?
When watching FMA Brotherhood, when van Hohenheim is talking to Pride, he refers to him as "プライド (Puraido) when he is talking to him by name, but when he is listing the seven deadly sins, he uses the term "傲慢", which is pronounced "ごうまん" (gouman). Is there any indication of why the character name is different from the term itself? This is probably true for all seven of the Homunculi, but I only noticed it specifically for Pride.

This is a simple "English is cooler"
As all the homunculi are named with the english seven deadly sins, their names are the hiragana/katagana representation to the english vocalization.
but when referring to the sin itself the correct translation ("傲慢") is used, as it is not a name (that also has to sound cool), but the thing itself.
I verified this is true to the other homunculi too, though not for "Father"

They do call father "Otou-sama" which is Japanese for "Father".

@MadaraUchiha glad i wrote "almost", btw. how does he refer to himself?? surely not as the dwarf in the flask...

@MadaraUchiha "otto" is Japanese for husband. "otou" is Japanese for father.


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Is it necessary for Amestrians to die for the transmutation circle?
Throughout FMA: Brotherhood, fighting has been breaking out, having been orchestrated by the Homunculi to power the giant transmutation circle that makes up Amestris. In most if not all of the fighting, it seems to be that the Amestrians are suffering great numbers of casualties. The fighting at Fort Briggs, for example, was orchestrated so Fort Briggs would be weak so they could be massacred. It is necessary that Amestrians to die for it to work and that is why it is being set up so they are on the losing side, or is there some other reason, like it is easier to make the Amestrians lose?

sorry, what exactly is the question??

The question is whether Amestrian souls are needed to power the transmutation circle.

No, it doesn't have to be Amestrians.
In fact, the fighting at Fort Briggs was orchestrated so that there were casualties. Kimblee was told by Pride that he simply had to create the blood crest. Kimblee knew that Briggs was stronger than Drachma, so he lied to the Drachmans and told them that Briggs was vulnerable, resulting in their entire army being destroyed.
In most of the other wars, in fact, Amestris was victorious. You have to remember that Amestris started as the green area in the map below.

They colonized the rest of the area around them (numerous existing places, some are listed in the Fullmetal Alchemist Wiki's article on Amestris) to enlarge the country for Father's ultimate purpose, in order to gain the amount of souls necessary. These victories often resulted in the deaths of far more innocent people and opposing armies than Amestrians.
So, to answer your question directly, no, it is not necessary that it is Amestrians who die for the transmutation circle. In fact, Drachmans, Ishvalans, and many others have been the victims of bloodshed for the hundreds of years prior to the Promised Day.


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How did Homunculus come into being?
In FMA, the being that became Father, the one known originally as Homunculus or the Dwarf in the Flask, seemed to have been created by Van Hohenheim's master using some of Van Hohenheim's blood. Is the creation ever explained in any greater detail?

The creation is never explained in excruciating detail. However, we do know that Homunculus was originally part of the entity within the gate (God, essentially, the being who regulates all alchemical exchanges). Through an unknown process, Van Hohenheim's master was able to isolate the knowledge within God.
He was able to give it an existence through the blood of a human (Van Hohenheim), which I speculate was used as the toll to reach into God's domain. However, this existence was not stable enough to take form, and thus cannot exist outside of its flask.

Unfortunately, we hear little from Hohenheim's master, and none of it relates to Homunculus. There is never a further elaboration on the process that is used to isolate part of within the Gate.


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Why is Ulquiorra's Cero green?
Normally, all of Ceros are red in color, but why is Ulquiorra's Cero was green?
Does it mean that it's more powerful? What makes it so different?

handwaved... extremely handwaved. also keep in mind that coyote stark's cero is blue/white

It is true that the default color for the ceros is red, but this color is usually used by normal Hollows or Menos.
But there is a o lot of Arrancars and Espada that use a different color of Cero, it is not just Ulquiorra, see this page here.

Most Cero are a crimson color when used by Hollows, Visored or
  Arrancar. While most Cero are commonly crimson, several Arrancar have
  shown various colors.

It also says:

The power, force, speed, and blast area of the Cero is dependent on
  the strength, spiritual power, and sometimes skill of the user

So, the color does not influence directly to the power of the Cero. In fact, the color changes depending on the user's personality and style. Ulquiorra's cero maybe stronger, but it is not related to the green color, but in Ulquiorra himself.


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What are the powers of the Sword of Nunoboko?
I have a few questions regarding this sword recently seen in Naruto manga (Chapter 651).
1st: How was this sword formed? I can see that it doesn't belong to the Treasured Tools of the Sage of the Six Paths. Is this forged or just formed from a special Chakra?
2nd: Does it have special abilities like the Sword of Totsuka wielded by Uchiha Itachi?
3rd: Does it have any connections to real-life history? Like the Treasured Tools of the Sage of the Six Paths related to the Chinese classic Journey to the West?
I have done an extensive research, but have not found anything useful. The wiki contains only its appearance and description from the recent chapter.

Check out this excellent post from Amaterasu's Son

Madara once said will cannot be passed down.
I propose that he was right to a degree. Obito never met the Rikudo
  Sennin, he never saw him with his own eyes, he never heard his voice
  or touched his heart. Rikudo Sennin couldn't pass down his will to
  him.
"His passion and intensity, permeate throughout the blade...you could
  say this blade carries his very essence."
Therein lies the problem.
Obito has no passion. He has no intensity. He has purpose, he has
  desire, and he has determination. But emotionally? He's an empty husk
  scratching to reclaim his own life as he envisions it.
But Obito cannot use that sword. You can't borrow Rikudo Sennin's will
  and passion and subvert it for your own use. If what Obito said was
  absolutely true then that sword breaking was absolutely foreseeable.
  Lest Obito forgets Hagoromo chose his younger son to lead the way to
  the future. Of the little we know about Rikudo Sennin we know that he
  has already rejected Obito and Madara's past thousands of years before
  they were even born. So if it is his essence in that blade, then
  clearly it broke on purpose because it wants Obito to lose.
If Obito was simply speaking metaphorically then it broke because he
  does not have the will and emotional vivacity to use such a weapon.
  For a man with no heart and no identity, using a sword that was
  supposedly comprised of passion is completely impossible.
Peace.

In other words, the Sage used his sword to create the world, life, friendship, etc. Obito is trying to use the sword to destroy all of that, but the sword simply cannot be used for those purposes. This is why the sword broke.

UPDATE: I realized this answer isn't entirely answering your question and that is partially because there are no definitive answers to your first 2 questions. Unfortunately, I don't know about Japanese/Chinese history to answer the third.
To answer the first, I believe anyone who has similar powers to the Sage of Six Paths can create one. So far, we have seen Obito wielding Rikudou Sennin's, Madara with his own, and this might be a stretch, but Naruto+Sasuke with their mighty sword.
Basically, the sword is a materialized version of the creator's will. By this, I mean that one of the requirements to make this type of sword is a very powerful will from its owner. I believe the sword Naruto had defeated Obito's sword was only because Naruto's will was stronger than Obito. Similar to what Amaterasu's Son was saying, I think Obito and his sword was not as powerful because the user himself did not have the will of fire.
Now let's talk about the abilities of this sword. All we know is that Obito said the Sage of Six Paths created the world with this sword. Madara's version for Obito also had his will in the sword. So despite not knowing exactly what the abilities are, we know that the sword's abilities will help accomplish their goals / will. Rikudou Sennin's sword was to create the world of peace, so that is what his sword abilities will complement. Although we don't know what exactly Madara's goal is yet, we do know he has some sort of evil plot to control the world. His sword will help him accomplish that goal, which is why he also passed it on to Obito.
Analysis / discussion link to Madara's materialized will here

Please add a link to wherever you took that post from. Not only it is polite, but some people might want to follow on the rest of the discussion there :)

Done. There might be inappropriate language / images on Narutoforums, so I didn't link it at first.

Now I just await Uchiha Madara's confirmation on the black pole of doom.

The answer to your first question is that it was made by pulling the truth-seeking orbs surrounding Obito into the sword form it takes. This makes it formed from special chakra.
Second, all its special abilities come from it being made of the truth-seeking orbs, so see that page for special attributes.
Judging from the lore and legend behind it, and its name, I think it is supposed to be the Naruto equivalent to the Amenonuhoko (literally: heavenly jeweled spear), the weapon Izanagi used to make the world. All Obito's talk about the sword is grandstanding. It's just an awesome sword made from truth-seeking orbs. Naruto and Sasuke broke it by being just that strong and having lots of sage chakra to make that strength effective.


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How much time does the original Fullmetal Alchemist anime cover?
I was always confused with something in the original (2003) Fullmetal Alchemist anime.
When Elric brothers have helped the Hughes' when Alicia was born, that happened around the same time when Edward have become a State Alchemist. If I know well, he was 12 in that time. It was in episode 6.
Most of the following episodes (Barry incident, the Chimaera, etc.) seems to cover a relatively short time. However, later it was mentioned that Ed is 14-15 years old. And also, I'm absolutely sure that it was true at the time when Hughes was murdered.
Which is the exact timeline order of the event in the episodes? First episode is obviously an introducing one, and second is the beginning of everything, and then?
Also, how is it possible that Edward looks totally the same in Episode 6 (where he was 12) and in Episode 50, for example (where he was 15)?

Please note: Much of this information does not apply to Brotherhood.

The order of episodes goes something like this:

Episode 1 flashback

Transmutation of Trisha

Episode 28 flashbacks

Initial alchemy training under Izumi
Pre-automail for Edward

Episodes 3 through 9

Barry the Chopper
Shou Tucker and Nina
Etc.

Episodes 1, 2, and 10 through 51 (not counting flashbacks)

Main story

The Conqueror of Shamballa

I have missed a few brief flashbacks here, but this is the general idea. You can use Edward's age, somewhat, as a marker of time passing. He is ~11 in the flashbacks of their mother, 12 during his State Alchemist qualification, and turns 15 prior to the main story (the incident in Lior, etc.). He is 18 during The Conqueror of Shamballa. (This is shown by 14-year-old Al reverting to being 10 years old, then aging to 13 when Eckhart starts breaking into Amestris. Since he is one year younger, and would be 17, Ed is about 18.)
Here is a handy chart for a full comprehensive view of the series (click to enlarge, or click here for the spreadsheet). Note that Edward does have a birthday in the main timeline, when he turns 16.

(Orange = pre-anime; yellow = flashbacks; green = anime series; blue = post-anime)

To address your point about Ed's appearance: Edward doesn't actually look the same at 12 as he does at 15. At 12, his eyes are slightly larger and his face is a bit rounder, save for his chin, giving him an overall slightly younger and more innocent look. It's not generally noticeable in the more zoomed-out shots, but it's there. (Also remember that, to perpetuate the "shorty"/"chibi" jokes, he couldn't grow much, so all the changes are facially.)

(Left: 12-year-old Ed, episode 4, 6:45; Right: 15-year-old Ed, episode 10, 13:50)

Wait, wasn't Episode 2 also a "memory"? I mean, if i can remember well, that wasn't the part of a main story, but just the events before the transmutation. (but in fact, I haven't seen 2003 anime for ~5 years, so I may be wrong :P)
Also, thanks for the chart and for the comparison! Indeed, while watching the whole series, the difference isn't so noticeable, but in these pics, it's perfect. Surprising fact anyway, good to know.

Episode 2 has some events in Lior ("present day") as well, but it is comprised largely of flashbacks, yes.

OFF: as I watch your most upvotes answers, I start to miss an additional letter "l" from your username ;)

@ZoltánSchmidt lol! I like that!

@Eric wasn't episode 2 the continuation of Episode 1 in Lior cause i remember episode 1 ending with Cornelo saying "You are the Fullmetal, the Fullmetal Alchemist!" and episode 2 Ed learns the stone is a fake, Cornelo confronts Lust before being eaten by Gluttony and Envy arriving as Cornelo and pull off some trick to make it look like he brought them back to life, quite sure episode 3 starts off present day but goes onto flashbacks when Al shows ED a beginners book on Alchemy

@Memor-X Yes, as I said, Episode 2 also takes place in Lior, but has several flashbacks.

The series starts three years after Ed became state alchemist. That means he was twelve when he became state alchemist and was around 15 or 16 when the manga/anime starts. At the end of the main story, he was 18 and twenty in the epilogue (when they start traveling around).
Here is a timeline for the 2003-anime: http://64supernintendo.deviantart.com/art/Fullmetal-Alchemist-anime-timeline-321323200

Here is also a (rough) timeline for the manga/2009-anime: http://fma.wikia.com/wiki/Timeline_Manga_/Fullmetal_Alchemist(2009)

A couple of things: What do you mean by the prologue? You mean the Shamballa movie? Also, that deviantArt timeline isn't entirely accurate: It assumes that 1923 in Germany is the same as 1923 in Amestris, which can't be accurate; in Shamballa, when the Armstrongs are at Lior, Alphonse is 13 years old, after being 10 at the end of the anime. Yet, it states that those things happen 6 years apart (1917, 1923).

Prologue was wrong, it's an epilogue, I didn't notice ... And I mean the part before Ed and Al leave Resembool again to study alchemy (I think it it's only in the 2009-anime).

Yes, that is only in the 2009 anime.


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What is the song played in Operation 11: Fallen Angel Rina?
The song that Rina sings in the opening/ending -- is it an existing pop song in Japan or a song created just for the series?

This is a bit vague. Is there one specific song? Is this an opening or ending song, or just one sung during the film? I have never seen it, but I find your question a bit vague.

The opening and ending. It looks like it's the theme song.

Would you please move this questions somewhere else?

It's called "Fallen Angel's Love". The music is by Shinobu and written by Masamichi Kaneko.
[Sources: I checked the English version of the ending credits.]

The opening and ending. It looks like it's the theme song

The Opening song, written by Reiji Kitazato, is called "Girls and horny sluts", it's probably most definitely not an existing pop song in Japan. While Reiji Kitazato does music for other (non-hentai) series, like Gankutsuou, this is probably written specifically for this show.

While it's good, I mean the song Rina actually sing in front of concert

Not the theme song of cool device in general. It's theme song of all.


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How exactly is the Eye of the Moon Plan supposed to work?
First, I am wondering how exactly does this plan work in the Narutoverse?
When everyone is under the genjutsu, does that mean no one is actually living their own life? Or do people live their lives and the usage of the genjutsu just eliminates pain, suffering, and war?
Will the people starve to death under this technique? And if not, are they able to reproduce? And if they can do the above two, will this technique eventually cease when Madara/Obito die?
I'm just wondering if life can still continue under this technique? If so, does the technique ever stop?
Now on a more (deeper) philosophical level, how is this plan any different from Pain's total destruction plan? Both goals of the two plans are the same. They both want to end pain, suffering, and war.
Pain wanted to cause destruction to achieve his goal. Obito / Madara wants to put the whole world under a genjutsu to achieve their goal, and they are willing to cause total destruction in the process. Is there any real difference in outcomes?
The way I see it, pain is inevitable in human life. So then why bother with the Eye of the Moon plan if you can just kill the entire planet. I'm going to assume that if they have what it takes to execute this plan, they also have what it takes to just blow up the planet / eliminate all living beings.
This then leads me to believe that Madara and Obito just have psychological problems. Is this the reason why they are proceeding with this crazy plan?

I'm not sure if this post belongs here, but I know at the very least that some of these questions can be answered. And there probably is some reasonable explanation for the difference in plans between Nagato and Obito, but I just don't know it.

The Moon's Eye Plan is an endless dream of eternal peace. It is nowhere mentioned that the real world has to be destroyed to achieve it.

The difference from Pain's plan is that rather than destroying the world, it aims to create a perfect world, albeit in a dream.

It isn't mentioned, but what I am saying is that Obito declared war on the entire world. And he is willing to kill anyone that gets in the way of the plan. I never said the real world needs to be destroyed to achieve it, but rather asking isn't it much simpler to destroy the world because essentially the "endless dream" and destroying the world is the same thing here (from my perspective). No one is actually living their lives in both scenarios.

I will answer this question in more detail after a few days. Too busy with something else right now.

I'll be waiting for that.:)

that is a damn sh*tload of questions...

I'm prepared to read a nice long essay

:) Finally found the time to finish writing it. I had been planning to write an essay on this anyway since a few months, then this question came up, so I thought, "Now is the time." :)

Note: This answer is based on events seen up to Chapter 651, and contains unmarked spoilers.
Since the answer is long, I will divide it into several sections, first explaining the mechanism of the Infinite Tsukuyomi, then the background and philosophy, and finally answer the specific questions.
Mechanism of the Infinite Tsukuyomi
Use Itachi's Tsukuyomi as a reference to understand the Infinite Tsukuyomi. The illusion lasts for 72 hours as per the flow of time perceived in the illusory world, but for only a moment in the real world. Powered by the Juubi/Shinju's chakra, Infinite Tsukuyomi is a superpowered version of it, in three ways:

It draws everyone's minds into the illusion.
Its illusory space is designed in great detail, as desired by the caster.
In particular, people who do not exist in the real world can be created there.
It lasts forever as per flow of time perceived in that world.
The illusion appears to last for only a moment in the real world, but since it is endless, real world time doesn't appear to advance. Moreover, since everyone's minds have been drawn into the illusion, nobody is around to perceive the flow of time. This may also be a subtle cultural reference, since Infinite Tsukuyomi uses the moon to cast the illusion, and Tsukuyomi, the Moon God is associated with the flow of time.

To understand the Moon's Eye Plan philosophy, a background of the Naruto story is useful.
Background of the Naruto story
Kishimoto originally wanted to make Naruto a seinen manga, but was advised to make it shonen, so that it could be published in the Weekly Shonen Jump magazine. In my opinion, it still retains its seinen core in the plot, while using shonen elements in the narrative.
Amidst the action and comedy, it has explored various elements of human nature or philosophy, and conflicts between them. The characters in the story are also used to represent such elements. A narrative primarily focused on the philosophy would lose audience interest, so it is useful to have characters represent them. For example, Naruto represents how positive thinking and hard work can overcome adversities, while Sasuke represents how revenge makes a person blind letting others use him, and so on.
Objective of achieving a peaceful world
An overarching philosophical question asked several times is, "How to achieve a peaceful world, devoid of hatred and suffering?" Various characters have attempted to answer it in their own way.

Hashirama: Distribute powers evenly between villages, so that they won't fight over it.
Jiraiya: Some day, people will truly understand each other, and hatred  will cease. I don't know how it will happen, but I believe in my student to figure it out.
Nagato: Create a powerful weapon which people will fear and stop fighting. This peace is temporary, since people eventually forget the weapon's power, so they need to be reminded again.
Naruto: I will end the cycle of revenge and justice, which will lead to peace somehow.
Madara: Create a perfect world free of winners and losers, which will end hatred and suffering.

Motivation for the Moon's Eye Plan
Madara lost all his brothers in the war. He lost the Hokage title to Hashirama. His own clan rejected him when he wanted to protect them (according to him). He also lost to Hashirama at the Valley of the End. He then read the world history at the Uchiha shrine, which described how Kaguya Ootsutsuki ended all existing conflicts by eating the Shinju's forbidden fruit, but it only led to more conflicts. He realised that a world which creates winners also creates losers, such a world would always be at conflict, and any effort to end the conflict would cause more conflict. He was convinced that there is no hope to achieve peace in the real world, and hence, decided to achieve it in an illusory world.
Obito initially rejected Madara's plan, but seeing how the ninja system led to Rin's death made him lose hope in the real world, and convinced him to accept Madara's plan of creating an illusory peaceful world, where Rin doesn't have to die.
Answers to the specific questions

When everyone is under the genjutsu, does that mean no one is actually
  living their own life? Or do people live their lives and the usage of
  the genjutsu just eliminates pain, suffering, and war?
Will the people starve to death under this technique? And if not, are
  they able to reproduce? And if they can do the above two, will this
  technique eventually cease when Madara/Obito die?
I'm just wondering if life can still continue under this technique? If
  so, does the technique ever stop?

As explained above, the illusion lasts forever as per time perceived in the illusory world. The real world becomes irrelevant once the illusion starts.

Now on a more (deeper) philosophical level, how is this plan any
  different from Pain's total destruction plan?

Pain's plan was to achieve peace in the real world through the fear of a powerful weapon, although the peace is temporary. Madara's Moon's Eye Plan gives people no choice, they are forced into the peaceful world permanently. In my opinion, the Moon's Eye Plan represents the philosophy that peace is a state of mind, while the body is unimportant, since it draws people's minds into peace (albeit an illusory one), while their bodies left in the real world become irrelevant.
As a side note, Pain's plan seems influenced by the atom bomb in our world, though the author hasn't stated it explicitly.

Why bother with the Eye of the Moon plan if you can just kill the entire planet.

The difference between the two could be a long philosophical discussion unto itself, so I will cut it short using an analogy. To end a lung tumour patient's suffering, you could do:

Remove the tumour (Naruto's solution)
A lung transplant (Moon's Eye Plan)
Kill the patient (this question's suggestion)

Analogies are often misleading, but the key point is that the Moon's Eye Plan wants to create a peaceful world, which everyone can experience, which destroying the world cannot achieve.

This then leads me to believe that Madara and Obito just have psychological problems. Is this the reason why they are proceeding with this crazy plan?

There is nothing inherently crazy about wanting to escape the pains of reality in one's dreams, since this is quite common human nature. The following Calvin and Hobbes strip is one popular instance. Bill Watterson's cat, Sprite, died in real life around that time, and he realised that he could be always be with his cat in his dreams.

Concluding that Madara or Obito have psychological problems is a stretch, or subjective at best. In our world, it is quite common for one person to experience a problem, and then try to solve it for everyone. Madara or Obito could easily solve only their problem using Izanagi, Rinne Tensei, or limiting the Tsukuyomi illusion only to themselves.
Lastly, the war also represents the conflict between Madara/Obito's philosophy and Naruto's philosophy, and we know that Naruto would eventually win in some way. This could be Kishimoto's way of giving us another moral, that trying to solve real world's problems through an illusion is futile, and they should be solved in the real world.

i would like to mention that not all genjutsu stops the flow of tiem, look at Shisui's Kotoamatsukami, with that Itachi Uchiha was put under a genjutsu and that too in real time. So maybe there is something similar in the moon's eye plan.
The target believe's what the user wants them to believe without interfering with their day to day activities.

This answer is very well crafted. The only thing that bothers me and I don't know if I agree with is The real world becomes irrelevant once the illusion starts. If the real world becomes irrelevant, then all life will (eventually) cease to exist, and this isn't part of Madara's ideal plan. Unless perhaps life continues indefinitely in the genjutsu.

You see, time stops in the real world once the illusion starts. Nothing ever happens in the real world after that. That's what I meant by real world becomes irrelevant. In-universe, Hashirama also points out that falling into the illusion is the same as "dying". I am pretty sure this is what he meant, not that people would literally die.

@debal No, I did not say that all genjutsu stops the flow of time, but the Moon's Eye Plan uses Infinite Tsukuyomi, so it is reasonable that it behaves like Itachi's Tsukuyomi. Moreover, Madara, Obito and Hashirama have said a number of times that the Moon's Eye Plan will be the end of the real world, and my theory seems consistent with this. Let's just wait a few more chapters, Madara's "trump card" is still to be revealed, and he is already making plans to complete the Moon's Eye Plan. He will surely reveal some more details soon. :)

So, from an outside perspective, humanity just gives itself a huge Darwin Award and the giant, intelligent cockroaches that take over the planet in a few million years will have arguments whether the strange clusters of rocks are evidence of a previous sapient species.


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How Edward managed to escape from Gluttony?
In Episode 24 and 25 of Fullmetal Alchemist: Brotherhood, Ed, Ling Yao and Envy are trapped in a sub-dimension that was created for storing everything that Gluttony has ever swallowed.
Envy told that there's no escape, but Ed has found out something. What did he do exactly?
As far as I can get, he did human transmutation to open the Gate of Truth and by this, he can escape. But how is it possible? Since the sub-dimension is separated from the actual world.
Also, why Ed didn't lose anything when he opened the Gate again? Why Envy and Ling neither?

which anime are you in? the new or the old?

"In Episode 24 and 25 of Fullmetal Alchemist: Brotherhood"

Gluttony was created to be a second Gate of Truth but is only a failed copy. Ed had the idea that because they came there through the failed gate, they must be able to get back trough the real gate. It's just like creating a door back to Gluttony.
To open the Gate of Truth, he used Envys Philisopher's Stone and the old parts of the Xerxes mural to make this special human transmutation. The sacrifice for opening the gate was a soul of the Philisopher's Stone, which thanked him afterwards (because he freed the soul).

So it was not the same kind of human transmutation than the one that Elrics have done.

@ZoltánSchmidt It was close. The transmutation to create there mother was a transmutation of the "material" into another form, the transmutation inside Gluttony was the same, but without changing their form but only the position. I don't know, but I guess it's a similar principle.

They didn't lose anything because Ed used the philosopher's stone. To create copies of themselves in the real world and transfer their souls to the copy of bodies he created.
So, he had to pass through the gate of truth for deleting his old self from gluttony.
Envy and Lin must also have passed through the original gate.
Ed could have brought back his limbs that moment.

What basis do you have for this idea of yours that they "create copies of themselves"?


text:
Who are these characters in the end of the last episode's still?
The two similar looking guys on the left are most probably Ginkaku and Kinkaku Ebisugawa brothers, and the tiger must be Yaichiro. But who are the three female characters? They don't look like any of the other characters in this show. Is this perhaps a reference to another P.A. Works show or its crew?

(click the image for full scale)

Going counter clockwise from the top left:

Kinkaku (upper, older brother)
Ginkaku (lower, younger brother)
Suzuki Satomi (Benten, as a schoolgirl she wears the blue blazer and has her hair up)
Yaichiro (tiger ver.)
The Mom (of the four Shimogamo brothers, house mother ver.)
Yasaburo (cross-dress ver.)

Kouji Kumeta, best known for the Sayonara, Zetsubou-Sensei manga, did the original character design for the series.

That's what I first thought - Kumeta's style is very recognizable in this one!


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Why was Ed's arm strong but Al's body not?
At the end of FMA: Brotherhood, when Ed got his arm back, it was muscular, and he used it to fight. When Al got his body back, however, it was weak and emaciated, as it had shown to be throughout the show on the other side of the gate? Was it ever explained why this might have happened?

Firstly, it's worth noting that the difference in their strength is perhaps not as drastic as it appears. Though Al's body has essentially wasted away, you can see that Ed's right arm is significantly weaker than his left arm as he did not have it during during the series (or for several years before), in which he had a lot of physical improvement.

However, as you mentioned, we can still notice that there is a difference. Ed's looks normal, though somewhat skinny, while Al's looks like complete skin and bone.
Unfortunately, I can only offer speculation as to why this is. Ed realizes that it's possible that he and Al were somehow interconnected within the gate, which allowed him to provide nourishment to Al's body through some kind of connection.

However, assuming this is true, it's easy to observe that Ed remains fully nourished and Al is significantly more starved. By this logic, if we assume that Ed's arm, too, is connected to his body in the "real world", he could be nourishing that at the same rate as his regular body, while Al's body would only have received partial nourishment. Unfortunately, this is never stated in the series, so it's just a guess.
So, while it's not a complete or necessarily canon answer, the best I can surmise is that while Ed's nutrients are feeding both his own body and Al's, he is receiving the lion's share of those nutrients, allowing his arm to degrade at a slower rate (or not at all).

What episodes are from the four small images from?

@kuwaly All from episode 21, right after the OP.

Actually, weren't there some lines in the Brotherhood stating: "I'm eating for us both!"? And was later also mentioned that that is probably the only explanation why Al's body hadn't completely deteriorated and why Ed had such an apetite...

@DaMachk Yes, as I said in my answer, "which allowed him to provide nourishment to Al's body through some kind of connection." The point I am making is that the nourishment reaching Al must be lesser than that reaching Ed, for obvious reasons.


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What is Nara's Strategy?
Before the Allied Shinobi Forces HQ was

 destroyed and scene goes to the Four Hokages with Sasuke, Orochimaru and the others,

was there is a strategy from Nara to be executed. If so, what is this strategy?
As I remember when the scene goes back to the war,

 Naruto and others have difficulty fighting against Madara and Tobi with no any sign of Nara's strategy.

Haha,:) very interesting. UP!

We currently don't know what this strategy is. or it hasn't been explicitly mentioned as far as i know.

wasn't that the strategy to distribute kyuubi's chakra to everyone?

Nara's strategy had four components:

Shinobi Alliance create distractions
Naruto powering shinobi up with chakra
Locking down the Juubi with the Shika Ino Chouji combo
The entire Alliance will attack full force at the Juubi

Naruto comes into communication with Shikaku here, as he shares his great Nara Plan. He also stated that he has told the entire alliance his plan already. However, the entirety of the plan is not revealed to the reader just yet. What they are discussing in this chapter is simply creating the distraction.
http://www.mangainn.com/manga/chapter/95742_naruto-chapter-612/page_9
Phase 2 of the plan begins here as Naruto starts to transfer his chakra to the Shinobi Alliance.
http://www.mangainn.com/manga/chapter/96726_naruto-chapter-615/page_20
Then phase 3 begins. Chouji is the front line tank along with many others. Ino uses her jutsu to take control of Obito and slightly throw off the Juubi's attacks. And Shikamaru and his clan use the shadowbinding technique on the Juubi. Also note that Shikamaru suspects that something may go wrong with this strategy and (in the flashback) Shikaku basically tells Shikamaru he is going to have to make that decision when the time comes.
http://www.mangainn.com/manga/chapter/97954_naruto-chapter-616/page_13
Phase 4 commences and the Alliance begins their attack.
http://www.mangainn.com/manga/chapter/98410_naruto-chapter-617/page_8
That pretty much sums everything up about Nara's strategy. The only problem was that it didn't work. Obito, Madara, and the Juubi are too strong to be taken down by the current Shinobi Alliance. That's when Minato shows up, followed by the other Kages and Sasuke and then everything changes again.

Additional proof Shikaku understood the Kyuubi's chakra transfering ability.
http://www.mangainn.com/manga/chapter/97954_naruto-chapter-616/page_8
Shikaku first learned of it from Kakashi's experience here.
http://www.mangainn.com/manga/chapter/98410_naruto-chapter-617/page_5

It is clear that you are not up-to-date with the manga, so I'll put the answer in a spoiler block.

Shikaku  figured out how the chakra of the Nine Tailed Fox can be shared with other shinobis, giving them extra power, so that they can provide better backup to the main warriors.

Note: This is only an abridged version of the entire plan. The plan in action starts from chapter 614 of the manga, and then the next instance is in the last page of ch 615. Finally ch 616 shows it all.

As you say shikaku figured that out. there is nothing that indicates that Nara told him that. can you give us the chapter this is being told.

@Robin check the edit. Also Nara relays the message just in the nick of time.

@debal: You guys know that "Nara" is the surname, right? He's called Shikamaru (the son) or Shikaku (the father)

@Robin That's like saying Minato was the Fourth Hokage, there's nothing to indicate Namikaze had anything to do with it. I am sorry I don't really follow what you are trying to say.

@MadaraUchiha oh yes i do. :)


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How did the Sage of the Six Paths obtain his Rinnegan?
It is shown that the Sage of the Six paths was the first to have the Rinnegan.
Now for an Uchiha these are the stages of their eyes:

Normal eyes
Sharingan (activated after facing life threatening situation)
Mangekyo Sharingan (activated after a very close person dies)
Eternal Mangekyo Sharingan (activated after replacing the
existing Mangekyo Sharingan with another mangekyo sharingan)
Rinnegan (conditions for activation have not yet been mentioned)

All these stages have covered by Madara Uchiha, he took his brother's Mangekyo Sharingan to activate the Eternal Mangekyo Sharingan.
Now if the same logic was to be applied to the Sage of the Six Paths, then whose Mangekyo Sharingan did he take for his own?
He being the first shinobi should not have anyone to take a Sharingan from.

As details from Chapter 646 of the manga, the accepted answer is outdated. Please take some time to consider if there are any other more up-to-date answers.

Which part is outdated? I can't find anything in 646 that differs.

The answers to the titled question and the question within the post still don't change

@krikara While the current answers do fulfill most of the criteria, certain parts are could use some updates or revisions. Since this question has a fairly good amount of views, it's best to make sure the all of the information is fairly up-to-date for anyone that happen to stumble upon this. Instead of details of some (older) answer that was changed by a later retcon.

@MalicahCaruthers asking a question in comments or as an answer to a question is not encouraged. Please ask a new question using the "Ask Question" link.

Awakening the Rinnegan
I think you have misunderstood something here.
The Rinnegan was the original form. It required no activation and was permanent to the Sage of the Six Paths.
His children, the Uchiha and the Senju inherited the two different feats:

The life force and physical energy went to the Senju
The visual prowess and strength of chakra went to the Uchiha clan.

This visual prowess manifested in the Sharingan as a visible component of the Rinnegan. The Senju had some second components to the Rinnegan embedded in their DNA.
When one brings the DNA of an Uchiha and a Senju together, one can awaken the Rinnegan.
The problem now is that the possibility to awaken the Rinnegan (when they also have Senju DNA) is in every Sharingan user, but only "under the radar". To activate the Rinnegan, it seems one must go through different stages:
The Mangekyou Sharingan and the [Eien]{Eternal} no Mangekyou Sharingan
Madara accomplished this. By implanting Hashirama's DNA to his cells when he was close to death, he finally awakened the Rinnegan.
It may also be possible to awaken the Rinnegan without undergoing the two higher stages of the Sharingan, but that is only speculative. As of chapter 674 of the manga, the DNA of Hashirama (or moreover, Senju DNA) is not required to awaken the Rinnegan.

 Sasuke awakens the Rinnegan, even though there is no actual explanation as to why. It probably has to do with the fact that Sasuke is possessed by the reincarnated spirit of Rikudo's son.

Origin of the Rinnegan
If you read Chapter 646 of the Naruto manga, you can see

 the Ten-Tails' awakening. And when he opens his eyes, you should be able to notice that they have a similar pattern to the Rinnegan. Actually, the eyes look like a Rinnegan with some Tomoe 巴 scattered in the circles of the Rinnegan.

 We also witness the Ten-Tails' awakened form (the Tree of God), which uses a more complex form of the Preta Path when he absorbs the chakra of people he caught.

 From this information, we can conclude that the Tree of God/Ten Tails was the original "wielder" of the "perfect Rinnegan" (well, it hasn't got a name yet), and that most probably, the chakra was not the only thing the Sage got at birth.

Correction, Sasuke's Rinnegan was awaken by the Sage of Six Path. It was when Rikudo asked Naruto and Sasuke to raise their dominant hand.

@TendouKishi IIRC it was never explicitly mentioned, that the SOSP actually awakened the Rinnegan of Sasuke "himself". I'd still say that every piece of evidence points to the reincarnated spirits, but I think a discussion would be moot ;)

@Vogel612 +1 for your answer. I have to agree with Ayase , After sasuke receives chakra from the sage of 6 paths, that's when he awakens his Rinnegan. Yes, it's not explicitly mentioned in the manga, but in retrospect, this is how.

This question seems to be pretty complicated and is asking a lot of things, so I'm going to break this down piece by piece.
How did the Sage of Six Paths obtain his Rinnegan?
Well, we really don't know whether he was born with it or obtained it after birth. What's important to know is that he was the first one that had it.
The stages/evolution of an Uchiha's eyes
Regular -> Sharingan (1->2->3 Tomoe) -> Mangekyou Sharingan -> Eternal MS -> Rinnegan
You are right about the progression, however you are mistaken when you ask
Now if the same logic was to be applied to the Sage of the Six Paths, then whose Mangekyo Sharingan did he take for his own?
The Sage of Six Paths did not have the Mangekyou Sharingan nor did he take the Mangekyou Sharingan from someone. He had the strongest and final form of the eye : Rinnegan.
When the Sage of Six Paths had two sons, his powers were split between them. One was Senju and inherited the Sage of Six Path's body strength. The other son was Uchiha and received the Sage of Six Path's ocular powers.
Keep in mind that both sons only received a fraction of what the Sage of Six Paths had. This is why all Uchiha always bore the Sharingan, which is a younger eye form for an Uchiha and has a fraction of the power of the Rinnegan.
Thus when a person wants to awake the Rinnegan, the requirements are both body and eye. An example of this is Uchiha Madara with the Sharingan and acquiring Senju Hashirama's DNA. With both DNA from Uchiha and Senju, he can finally become a Sage of the Six Paths and obtain the Rinnegan. And even while using the Rinnegan, Uchiha Madara is still able to use Mangekyou techniques like Susanoo, which confirms that Rinnegan is the final evolutionary state of the eyes.

I believe your grasp of the dojutsu is flawed. Sharingan and Rinnegan are two separate jutsu, though one descended from the other. The final stage that an Uchiha can hope to achieve naturally of their Sharingan is the Eternal Mangekyo Sharingan. To achieve the Rinnegan, one needs to be born with the chakra of both the Senju and Uchiha as the Sage once did. However, this can be bypassed by acquiring the DNA of one and introducing it into another.
In short, the Sage of Six Paths was born with the Rinnegan. Seeing that it manifested itself naturally, he did not need to steal DNA (Senju) or eyes (Uchiha), as neither clans were present during his lifetime.


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What's the story behind the item Celty is looking for?
I know Izaya

 has her legitimate head, but how'd she lose it in the first place? She's also a Dullahan, so I don't understand why she even wants her head back?

 Shinra's father stole Celty's head when she was asleep, and gave it to Yagiri Pharmaceuticals.  Celty wants her head back because it houses her memories.


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What is purpose of these arm band?
In anime, people who in charge sometimes wear armband,

from left to right: Haruhi Suzumiya - The Melancholy of Haruhi Suzumiya (Club president), Suzu and Tsuda - Seitokai Yakuindomo (student council), Kuroko - Toaru Kagaku no Railgun (Judgement, Disciplinary Committee), Kamado Ueshita - Mirai Nikki (Director of the orphanage).
is this arm band have particular name? what is it purpose and how is this originate? Is this related to Japanese culture? I never see someone wearing this in my country.

from what i understand they show they are in a school club/group like a Student Council/Disciplinary Committee, the 3rd one is Kuroko being in JUDGEMENT which is like a Disciplinary Committee except city wide, not sure if it's a culture thing or not though

probably relevant: http://tvtropes.org/pmwiki/pmwiki.php/Main/RedArmbandOfLeadership

Arm bands in Japan, usually called as red armband, is worn as a method of identification of team/group or organization (more on this at the end)

The red armband can have a very different connotation in Japanese
  culture than in that of many other countries. The leader of any group
  might wear a red armband, usually with the characters for the name of
  the organisation written on it, as a symbol of his authority. Due to
  cultural diffusion, the usage of the red armband by leftist political
  groups has spread to Japan as well.

Source
The link also has information on how it spread to Japan but that's out of the scope so I'm not including it here.
Known bands from the picture:

1) Haruhi Suzumiya wears a band that reads Brigade leader

2) In Ousai (Private Academy featured in Seitokai Yakuindomo) red armbands signifies power, not
 leadership—students that enforces rules wear them.

3) In Toaru Kagaku no Railgun, this band signifies the Judgement Committee
Couldn't find information regarding the fourth.

Also, personally, in many Japanese Dramas I have seen working people wear such bands like the reporters, journalists, forensics and even the police officers (not red though, it's usually white in black text) so I'm guessing it's a way to tell who's from which organization.

While the armband Haruhi is wearing in the question does read "Brigade Leader", the one you've included in your answer reads "Super Director" - it's the one she was wearing when they were filming The Adventures of Mikuru.

@senshin Too bad I don't read Japanese. Thanks for the info. Is the above image correct?

Yup, that's the "Brigade Leader" armband.


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What type of weapon is Nnoitra's zanpakuto?
In the Espada Arc, Kenpachi fights Nnoitra.I was trying to explain Nnoitra to my friend but I couldn't figure out what kind of weapon it was, is it a scythe or what?

Nnoitra's zanpakuto, Santa Maria, is unique in regards to what type of weapon it is.
Unreleased, it resembles an axe with two crescents or a halberd, with it's edges rotated by 90 degrees.

But due to the placement of the blade edges, it resembles a scythe more so than an axe.
When released, it resembles a scythe:

But note that when he was the 8th-ranked Espada, his weapon resembled a staff with a giant crescent:

Note that it does a similar motif to the Chinese monk's spade (aka Crescent Moon Spade) weapon that's like a halberd.


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Why are there different words for "manga" and "manhwa"?
So lately I have been noticing that a lot of people on fora tend to mistake manga and manhwa. And of course, I know that manga stands for comics made in Japan, and manhwa for comics made in Korea.
But what is the reason for the different naming? Or is there even a reason besides them coming from different lands to begin with?
In the end they are both comics with usually (a bit dependent on the artist/writer of course) same art/story building and the like.

I believe Manhwa is simply the Korean word for it.

@MadaraUchiha Then why do so many people make a fuzz off it? Some anime related sites even ignore the whole existance of manwha (myanimelist) as if its a total differnt entity

@Dimitrimx It's the same reason why people make such a fuss over "anime" vs "cartoons".  Of course anime and cartoons are the same thing.  Some people just want to make themselves feel special.

Briefly: manhwa is the Korean reading of the word 漫画, while manga is the Japanese reading.1 In their respective languages, both words basically mean the same thing - "comics". In English, we use the Korean reading manhwa to refer to Korean comics, and the Japanese reading manga to refer to Japanese comics.
Why do we have different words for these things? Because manhwa and manga are not the same thing.

To explain what I mean, let me backtrack a bit and talk about why we don't just call manga "comics". I know that these days there's something of a backlash against the idea that "manga" is a distinct thing from "comics", presumably a reaction against '90s-era weeabooism and orientalism that identifies Japanese art as some sort of elevated form that is beyond comparison with the art of the West.
There is a kernel of truth in this backlash, but it's been taken too far. Reasonable people today will probably agree that there isn't anything about manga that makes them inherently superior to Western comics - but it is certainly the case that manga and Western comics are different. In fact, aside from being of the same medium, manga and Western comics (for the most part) have essentially nothing in common! Art styles, typical plots / subject matter, character archetypes, form factors, publication methodologies, etc. all differ between manga and Western comics.
Now, manhwa and manga are more closely related than manga and Western comics, but the same principle still applies - there are salient differences between the two forms, which is why we often talk about them using two different words. Foremost among the differences is the fact that they're largely written by two different groups of people, and thus tend to reflect the interests of two different cultures. (Try telling a Korean person that their culture is basically Japanese, or vice versa - they probably won't be happy!)
In closing, I will reply to this claim of yours:

In the end they are both comics with usually (bit Dependant on the artist/writer off course) same art/story building and the likes.

There's more to art than just medium. Medium matters, but so does content, and it would be a gross oversimplification to claim that content of manga and manhwa are essentially the same.

Notes
1 More or less, anyway, modulo issues of character simplification.

There is a pretty strong argument for the superiority of Manga over Comics and you can read it here: https://www.quora.com/Why-is-manga-viewed-as-better-than-comics

As senshin's answer said: though the medium might be the same, many things like processes, styles, story writing, country, etc. are different.
Conveying different art/writing styles
In my opinion, it's not even just a matter of X artwork/writer coming from Y country, but about how to convey the styles when introducing it to different people that may/may not know the works. It is because calling all of them "comics" would cause half the people to only get a vague idea about it if they don't know the style & name of the works called in English & not Japanese/Korean even if they accept that all works can be called "comics" in English, just like comics are called "manhwa", etc. in their language.
But if you use the word "manga"/"manhwa"/"manhua", people are more likely to be instantly conveyed of what style it is. So, the precision of words can give either instant recognition or confusion. So, not calling everything (manga, manhwa, manhua, chitra katha (Indian comics), webcomics/webtoons (webcomics on Line webtoons/other apps)) as "comics" may reduce some confusion.
Confusion due to generalization of comics
Half people are going to be confused as to what people are talking about.
Personal experience: I know a person who I had to handle really carefully because they thought I was talking about Marvel/DC (because they thought webcomics = American comics (DC/Marvel) whose art styles they disliked.
Generalization process: In America, those styles were more popular because a lot of people preferred a ratio of more action & less depth/psychological emotions back then, compared to mangas/manhwas.
So, the same was more popularized & distributed around the world too, sadly generalizing its format.
It took me a good amount of explaining & showing the photos carefully to make them understand that no, it might be the comics as a medium, but comics as American comics & manhuwas/manhwas are very different things. So, they don't get totally averse to checking it out.
While even if they didn't know what manhwas were, they wouldn't have automatically presumed I was talking about comics & might have shown a bit of curiosity as long as I didn't use the word comics.
Difference in contexts & perspectives
So, we need to understand that the same word might mean something totally different according to context & person's social conditioning.
Alternatives
The other alternative is to call them "American comics", "Korean comics", "Japanese comics", "Indian comics", etc. But that's long & it's ok if you want to introduce it to different people that don't know the words manhuas/manhwas/mangas. Otherwise, just using their original countries' names is easier even if you speak English.
Global bending in of writers.
Works' names are not about the writer's origin anymore as writers ―regardless of the country― make works of each other country's style, e.g. Japanese writers may make manhwa-style webtoons & American writers may make Korean-style webtoons & vice versa.
We can convey hybrid blend styles by just saying it's a mix of manhwa & manhua (e.g. The God of High School has a manhwa style artwork & anime/manga style writing). That too doesn't need to be stated as much unless the work is too different.
What each main/subcategory term instantly signifies.
Anyway, just know that when people say:

Comics, they think of DC/Marvel (with exception of webcomics/webtoon readers).
Manga reminds them of greyscale Japanese mangas.
Manhwas reminds them of older physical Korean manhwas (if speaking to Koreans) + webtoons/webcomics (for people that read them).
Manhuas reminds people of ancient Chinese historical kinds of webtoons/webcomics (literally historical Chinese drama turned into comics).
Graphic novels which are a bit different from comics as well.
Light novels in Japan are different from just novels in the west.

Other causes of fuss: misnaming.
Many make a fuss because that's what they're used to hearing & acknowledging it as. So, it feels like misnaming something important they like/generalizing something unique.
Imagine human misnaming that feels similar: like when people are annoyed a bit when someone calls your name differently & that name is similar to someone else's name once, then super annoyed when they keep hearing it as if that's your real name.
It feels like misidentification/attack on your identity when another person has no such intentions (usually unless someone's doing it deliberately for teasing purposes).
Generalized/over-simplified presumptions made about a work based on types of works.
Imagine this conversation:
A: Hey, wanna read manhwas/webtoons?
B: (doesn't know what it is via experience/imagery so they presume) Oh, it's just comics, right? So, nah.
It hurts to hear that because American comics & mangas/hwas/huas may offer 4 completely different experiences. For many, manga/manhwas have been life-changing experiences. So, it hurts them to see people presume it's something they know & not a big deal without giving it a chance, even if it's nothing personal.
E.g. people thinking some shounen anime is just superhero cartoons & if they've already watched too many superhero movies/works, etc. they're tired of that genre & ignoring it. When genre-wise they might be similar, Bleach/Naruto/One Piece/My Hero Academia are different from Superman/Batman/Spiderman/Green Arrow. Some may like one more than the other, but they can be substituted easily, though maybe some prefer My Hero Academia that's closest to superhero works.
Comparison of superiority (sometimes unfair), another reason for fuss.
Because though now American comics are online webtoons too & offer a lot more than just DC/Marvel like comics, sadly they aren't as popular.
As many like/prefer/consider manhwa/manga styles better & though sometimes it's true that manga/hwa/huas have better art style & diverse writing, it's not always the case, and though unlike some people, I didn't look down on/totally dislike American comics.
I used to wonder if American comics only have generic superhero stuff in it with similar storylines & I wished for something different in art styles/storylines. Though I knew that maybe there's a minority of different works that, I don't know. That is until I read some chapters of many underrated comics like Sithrah/Space Boy, The Strange Tales of Oscar Zahn, Brothers Bond, etc. on Line Webtoon. They may still have that original American messy, edgy styles which do suit them & make them unique even if I still like manga/hwa/hua styles better.
Diverse context-wise reasonings.
The point is, without context & asking the person's reasoning for their beliefs/unless we know which of circumstances they fit in, we can't fully presume just one reason as to know why they make a fuss about it. We can only guess a bit according to the circumstances I gave (whichever fits them better) & then ask their reasons.
Online aggresion.
Some people getting excessively hyper about it & getting too aggressive about it isn't ok.
Middle ground/nuances: because I'm stating the reasons, both sides understand each other's reasons & both change their approaches/find a middle ground than insisting that they're right. People that want to call subcategories by names have practical reasons apart from just misnaming/respect/habit though. So, I personally prefer mentioning subcategories. But it doesn't mean I'm going to be as fuming as some people if someone missed it. Just that it'd cause me to type extra sentences & ask them what kind of work they're talking about & it can be a confusing conversation if someone calls every subcategory "comic"/"manga" due to misnaming. I hope that people that get extremely angry when it's misnamed can understand why other people say it too so they can strike a communication & explain why proper naming may reduce confusion.
Manga/anime are generalized too: yes, some people have a habit of calling everything "picture story"/"animation related" a "manga"/"anime" because similar to comics, that's a generalized word & because they don't know another word for it. And when they're introduced, they aren't habitual to it enough, so they forget.
e.g. animation style of/in:

America = cartoon
Japan = anime
Korea = aeini
China = donghua

But since only anime is worldwide popular today, succeeding cartoons people use the word "anime" for aeini/donghuas too (which aren't as different as cartoon & anime)
Hope I covered some other points other than which senshin made.

Similar example of cartoon & anime
Avatar the Last Airbender debate
E.g. How there was a lot of debate over if Avatar the Last Airbender is a cartoon or an anime when it's a mix of both style-wise, like a cartoon-anime hybrid, but there is no word for the blend, hence the confusion.
Word for anime & cartoon hybrid blends.
I too was confused about what to call it, cartoonime/animetoon/carnime... none, except "animetoon" came naturally because maybe I've heard that word before somewhere. But calling it a blend/hybrid of both suffices to explain what it is too. But most people lean towards anime due to its style being so similar to anime. And I try to add that it's a blend when I can so I don't discredit the cartoon side.


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Who created the Uchiha's Clan's stone tablet in the Naka Shrine?
Deciphering the Uchiha's stone tablet, located in the Naka Shrine, requires the Mangekyou Sharingan or Rinnegan. However does the creation of the tablet require a Mangekyou and Rinnegan?
Rikudou Sennin had the Rinnegan and one of his sons who inherited his eye-techniques as the Mangekyou Sharingan.
What type of person was capable of creating this tablet?

I don't think the manga mentioned anything about who created the stone tablet or what type of person is he/she. Answers to this question would be merely speculations. Let's just wait until Kishimoto Masashi-sama mention about it.

@Sp0T: Wrong thread? :)

It's revealed in today's manga( ch 671) that Rikkudou Sennin created the stone tablet.

this question needs a change in accepted answer, or the currently accepted answer needs an update.

Now, in manga version of naruto (Chapter 671 Page 6), The Sage of Six Path mention that he left the stone monument so that people could reconsider. This is a concrete evidence that the Sage really created that stone monument. See image below (Spoiler alert):

Kishi never explicitly stated in the manga that Rikudou Sennin created the tablet, however we can make an educated guess that he did.
Let's take a look at the facts.

To read the entire Uchiha tablet, the Rinnegan is required.
Madara is stated to be the second Sage of the Six Paths. (This should mean no one else had the Rinnegan inbetween Rikudou Sennin and Madara.)
The tablet had an extensive list of things, like the Moon Eye plan, how to obtain Mangekyou Sharingan, how to obtain the Rinnegan, and the history of the God Tree with Kaguya.

Kaguya could not have written the tablet because most of the tablet's info pertain to Rikudou Sennin's era, where he had the Rinnegan and was the Juubi Jinchuriki. And since Kaguya isn't considered to be a Sage of Six paths, we can assume she doesn't have the Rinnegan either. We can also assume that a Rinnegan user must have written the tablet.
With that said, Rikudou and Madara are the only two candidates left, but Madara uses the tablet to learn about the history of Shinobi, so Rikudou is the only one who could have written the tablet.
EDIT: Additionally, Tobi stated the Sage of Six paths created the tablet here (bottom panels).


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What happened to the Dragons?
Dragons are assumed to be myth or somewhat a legend in someway in Fairy Tail. They also disappeared in Fairy Tail. But what was the reason behind them disappearing. We have seen in an episode that Grandeeney and Igneel are still very much alive, but seem to look as though they are in hiding. Also what's up with all dragons disappearing on the same day and the same year?
Answers are appreciated :). If there's anything from the manga, please include in answer. I do not think they have covered it in the anime.

There's no need to include a spoiler warning in you post. if you have spoilers, please use the >! spoiler markdown to enclose you content. E.g., >! spoiler here!

Additionally, if you mention an episode, please try to indicate which episode so people can get on the same page and don't have to guess which episode you're referring to.

So far, little has been revealed.

On July 7, X777, all the Dragons, except Acnologia, seemingly vanished, most notably, Igneel, Metalicana, and Grandeeney, who each abandoned their young foster children, leaving the species to be remembered as little more than a myth.
To the events of the year X784, society does not believe in the existence of Dragons. However, the destruction of Tenrou Island caused by one of them, called Acnologia, changed society's view on this issue.

http://fairytail.wikia.com/wiki/Dragons

There were several reasons why the Dragons disappeared at that time and it was revealed in chapter 415.
In the end, the dragons were indeed still alive. They hid themselves inside the dragon slayers' bodies. The reasons behind this were threefold:

The dragons were afraid a new human would become so powerful that he would transform into a dragon, just like Acnologia. To prevent this from happening they went inside their bodies to slow down their power increase.
The second reason was that the dragons were waiting for the right time to defeat Acnologia. Despite this reason clearly being stated by Grandeeney, I have a hard time believing it. Especially since the dragons did not fight Acnologia at all. They just watched Igneel get defeated. If they had attacked together, they might have been able to do more damage I believe.
The third and probably main reason why the dragons all disappeared was that Acnologia used his magic to extract their souls from their bodies. In order to prolong their lives, they retreated their souls (and apparently their bodies too) inside the dragon slayers they had once raised.

As far as I know, all the dragons left there foster children (Gajeel, Wendy Natsu) because they didnt want them to turn into dragons. it explains later in the show that if a dragon slayer becomes powerful enough, he/she can actually turn into a dragon. They didn't want this to happen, so they went into hiding.


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What happen in episode 13.5?
After the last episode (ep 13),

 Everyone graduate except Otonashi and all the NPC disappear, but there's episode 13.5 where Otonashi become student council president replacing Kanade place, and all NPC and one regular student (non-NPC) appear again. Did they reset the after life world?

What exactly happen here?

The so-called "episode 13.5," titled "Another Epilogue" was released as an extra on the BD/DVD exclusive. Depicted is an short alternate ending where Otonashi remains in the school and becomes the new student council president, in order to help other students (like how Tenshi did) to pass on. It's really a "what-if" scenario rather than an actual epilogue.

so the actual epilogue will be Otonashi graduate with Kanade right after she graduate?

It is implied that way, yes.

I was about to accept your answer then I realize something, your answer seems to explain that this is only alternate ending but didn't explain what happen here, or am I missing something? Did they reset the after life world and Otonashi choose to stay or what?

As I said in my answer, this is an alternate ending where Otonashi remains (instead of passing on) in the school and becomes the new student council president. Nothing reset, no one chose anything... it's merely a what-if. What if Otonashi remained, like the creator of the system Tenshi uses.


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Where does the flow of power come from for a Transmutation Circle to work?
On the Full Metal Alchemist Wiki under the Category  Alchemy. It says this...

The circle itself is a conduit which focuses and dictates the flow of
  power, tapping into the energies that already exist within the earth
  and matter. It represents the cyclical flow of the world's energies
  and phenomena and turns that power to manipulable ends.

But does this energy not come from a parallel world on the other side of the gate where alchemy took a different form of science? Did it not come from the lives of those who died in that world? Or is this different in FMA Brotherhood, because I am certain this is what Hohenhiem told Edward in the FMA Anime (2003).
Answers are appreciated. :)

it is different in Brotherhood as Father (Dwarf) taught Alchemy to the people of Amestris in a way where he could shut down all Alchemy himself (as if he was god), Xing's alchemy called Alkahestry which Von Hohenhiem taught operates differently so even after Father shut down everyone's Alchemy, May could still use her Alkahestry to help the Elric's escape

Yes, It's different. The original FMA anime didn't wait around for the manga to catch up (like DBZ did), so it diverged instead.
What you ended up with was 2 completely different endings, and 2 different explanations for why alchemy works:

In the original anime, the explanation was that It came from the other side of the gate.
In the manga and in brotherhood, it came from energy that was already in the earth.

I believe Alkahestry (the other form of alchemy from a different country called Xing) was powered by this thing called the 'Dragons pulse' (essentially tectonic movement) and the Father's philosopher's stone powered alchemy in Amestris, at least in Brotherhood it did.

Regular alchemy was powered by tectonic movement. That's why Father, who controlled the tectonic movements within Amestris, was able to "turn off" the Elric's powers, but Scar's and May's powers (which derive from alkehestry) were unaffected. We don't know how alkahestry is powered, it's never really explained other than it comes from the "dragon's pulse", as you mentioned.


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How did Mikoto hold his breath for four minutes?
In the 3rd episode, Yousuke asks Mikoto to hold his breath for 3 minutes by indulging his head into a bowl of water to let him join the bicycle club. After one day of training, Mikoto manages to hold his breath for 4 minutes. When Yousuke asks him how he achieved that, Mikoto answers that he replaced the water with soda to be able to do it.
I don't understand how using sode instead of water would help someone to hold his breath longer. What is the explanation for this?

I'm wondering if it's possible an anime physics thing regarding the bubbles in the soda, disregarding the fact that they're not actually breathable.

I did not watch this Series, nor could I find a official source stating this. This is just a theory I deduced.
Considering he said "see, because it's harder to drink soda." He most likely figured: If you drink, you hold your breath. If you drink soda it's harder/takes longer. So I can hold my breath longer. Looking at the response of him and the people he says it to I find this to be one of the best explanations.
Then the actual physics behind it for him to actually manage to last longer due to this :

The air we breath is 21% oxygen. By inhaling 100% oxygen for a couple of minutes (enough to washout the nitrogen from the functional residual capacity in your lungs), you can pretty much hold your breath about 4-5 times longer than normal. Anesthesiologists routinely do this before putting patients out as a safety thing (hence the mask when you "go off to sleep") because in an emergency the patient can usually "hold" his or her breath for 5-10 minutes after breathing 100% oxygen. And this works because the patient is already unconscious and can't feel his/her CO2 level rising.
Doing this awake, however, is very difficult as you can feel that CO2 rise and even though your lungs are still full of oxygen your brain will be freaking out and demanding that you take a breath. It is possible to overcome that breath instinct, however, with some training or serious dedication. This is part of the reason that hyperventilation (really rapid deep breathing) before breath holding helps you hold your breath - you drive your CO2 level way down and it takes longer for your brain to reach the freakout point while you're breath-holding. This is also why it's dangerous to do so: while that CO2 level is rising again you may well burn through your oxygen reserve (and since your brain still feels fine with regards to CO2) you can lose consciousness from hypoxia. Fun, right?
Source

Short Summary:
Due to him getting used to the CO2 level Rising, his brain does not panic him to take a breath. So due to training in CO2 he most likely reduced the point of forcefully needing to breath to 4 minutes. Which is also about the max we can hold in with 21% oxygen.


text:
Is this Ghost in the Shell Volume complete?
I'm looking to buy the Ghost in the Shell Manga on ebay, and I'm confused.
On one hand, I see an offer for about 5€ for the book with the
EAN: 9783897485037. No page count or further info is given.
On the other hand, I see an offer for about 23€ for the book with EAN 9781935429012 and ISBN 1935429019, the last one also mentiones a page count of 368 pages.
Now, GitS was apparantly first published in a serialized form, and the first bunch of the series was then published as one book. This is what I want to buy. I'm worried that the first, cheaper book might only contain part of the series. I know that there's GitS 1.5 and GitS2:MMI, I'm asking about the first Volume. I lack the knowledge of the vast Manga-databases* where I can simply look up with my EAN/ISBN number what I'm looking at, can someone help?
Edit: I'm looking for German or English versions.
*They must exist, right?

You don't mention the language you are looking for.  The cheap one is a German translation if that matters.

Oh yeah, the cheap one was an anime comic, not the original manga. Not what I was looking for.

If you're referring to the manga by Masamune Shirow, there are 3 volumes the first volume was initially published by Dark Horse in the US. Currently all 2 volumes of the main series and the 1 volume "interquel (Vol. 1.5)" have been republished by Kodansha Comics USA
Volume 1 has:

Pages: 368 | ISBN: 978-1-935429-01-2

Volume 2 has:

Pages: 312 | ISBN: 978-1-935429-03-6

Volume 1.5 has:

Pages: 176 | ISBN: 978-1-935429-96-8

Most of these volumes are also available on Amazon.de (if not you can get them on Amazon .com), if that's more convenient for you.
Vol. 1, Vol. 2, Vol. 1.5

Are all the editions you mentioned complete (apparantly kodansha censored a recent edition)? Also, this is exactly the answer I was hoping for!

As far as those from this author, yes.