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What is Kirito's relationship with the girls of SAO?
In the first and second seasons of SAO, Kirito seemed to be interested in more than one girl at the same time. At the end they are all friends and such, but they are all jealous of him and he likes them back and all.
Some would argue Asuna is the real girlfriend, but:

In the cave with Sinon (SAO II, ep.11, 20:30), Sinon asks "Is there someone you don't want seeing this?" Kirito shyly answers no.
While introducing Asuna to Sinon, Kirito only said that Rika and Asuna were his friends. Asuna looked okay, a bit like she was thinking "Yeah I'm just his friend."

These two occasions got me wondering: is he playing them all at the same time or something?
What I'm asking for is something like a timeline, which shows when Kirito likes whom.

In light novel Volume 5 and Volume 6 - Phantom Bullet, it is confirmed that Kirito is going out with Asuna.

From Volume 5 - Chapter 1, when Kirito went to meet Kikuoka from the Ministry of Internal Affairs' Virtual Division for a talk regarding victims of Death Gun in GGO (emphasis mine):

“...Well, at least I’m together with my girlfriend.”
“I see, I am jealous to death over that one point, Kirito-kun. The next time we’re in ALO, wouldn’t you introduce me to some girls? Take the Sylph Lord for example, she is just my type.”

This conversation took place before they began talking about the cases related to GGO (B-part of episode 1, SAO II), and was cut off from the anime.
From Volume 5 - Chapter 2, after the meeting with Kikuoka, he met up with Asuna at the Imperial Palace for their date (emphasis mine):

“...Oh yes, why did you choose the Imperial Palace for our date? Kirito-kun, are you interested in history?”
“Well, not really. The main reason was... recently, I was called around here for some stupid business...”

This conversation took place before Kirito's talk about the closed network of the surveillance system in Imperial Palace (A-part of episode 1, SAO II), and was also cut off from the anime.
From Volume 6 - Chapter 9, before the final round of BoB (emphasis mine):

I really won’t dare to say this to a real person in the real world. No, considering that I already have a girlfriend in Asuna, it’s unforgivable even in the virtual world. However, I dare to swear to god that this isn’t about trying to get a date in the VR world, but to fulfill my duty and mission, and also a necessary step to ensure Sinon’s own safety.

This inner monologue took place when Kirito asked Shinon to explain the format of the final round of BoB, which took place between 30 players on a huge map (anime episode 8, SAO II).
I think this should be enough to show that Kirito and Asuna are dating in real life after the events in Aincrad and ALO.

Good answer; well cited. To augment this answer, perhaps Asuna recognizes that Kirito simply interacts well with other girls, that he's attractive to other girls, and seems to trust Kirito instead of getting jealous.

Referring to when Sinon asked Kirito " Is there someone you don't want seeing this?" and then Kirito replying "no" when they were in the cave during Bullet Of Bullets 3. He probably said "no" because he didn't what her to feel embarrassed because she was on top of him sexually(unintentionally). And he probably referred Asuna as "a friend" because of the same reason.

You're saying "probably". Can you provide any evidence to back it up?

In volume 1, Kirito and Asuna is the clear cut pairing to any reader, as there are no mentions of other girls in Kirito's life except mentioning that he has a sister, without going into detail about her. As nhahtdh explains in his answer, it is very clear that Asuna is the main heroine of the story, and that Kirito is committed to her.
So why are there so many other girls involved with Kirito?
Starting in volume 2, Silica, Lisbeth, Yui, and Sachi, were all side characters introduced to give readers the same feelings that the author, Reki Kawahara, felt when he played MMOs. As with most MMO players, he was never part of one of the top groups, and had great respect for players that could clear the hardest content or had the best items. This sense of awe that was instilled in him in games is the same feeling that he wanted to portray by showing some weaker characters and their struggles and then having a hero show up and really show them how badass someone end-game could be.
Kawahara notes at the end of the volume 2:

I have previously also played some online games. But no matter in what
  game, I have never been part of a high-ranking group. I merely envied those
  eternally strong players with the best equipment and reputation, one after
  another easily defeating monsters, and afterwards feeling that they were "So skilled! So strong!" (haha)
  Therefore, I wanted to write about not only the volume one's protagonists
  Kirito and Asuna and their  type of top players, but wanted
  even more to write something about the stories of ordinary mid-level
  players; and this second volume's four short stories, have precisely this kind
  of content. Regardless of which story, they are basically about Kirito
  debuting and causing a big stir; and feeling that he is "So skilled! So
  strong!" like Scilica and Lizbet felt, is precisely what I have felt every year
  since becoming an MMO player. Really, and once would be enough, I
  really want to know what it feels like to show off to others a weapon of
  which there are only three copies in the entire server.

Kawahara created many side stories which introduced these different female characters, all of which had their own backstories and troubles to be solved.
However, despite creating these girls and their problems, he always has one solution to their problems: Kirito. Since Kirito is the main protagonist of the story, Kirito was always the hero which would show up to fill this role of legendary MMO player. Kirito is the game's hero and all of the focus and glory shines on him and his perspective.
Additional comments on this matter by Kawahara in volume 2 Author Notes:

Besides that, there's one more thing that I must apologize to everyone about.
  Even though the four female characters in this book are all different female
  players, their male counterpart, as discussed earlier, was always Kirito-san.
  Even though there is no way for me to explain myself to everyone properly
  on this point, I painfully excuse myself, and ask that everyone please use
  the "even though the criminal and victim change every time, the detective is
  always the same person" mindset you have when reading detective novel
  series... you can't do it right? Sorry, sorry.

Since the release of Sword Art Online: Ordinal Scale (the recent movie addition to the series) it is safe to say the Kirito and Asuna are in a proper relationship,

 perhaps even engaged (I'm not sure of the significance of giving a ring)in Japanese culture.

He maintains his friendship with the other females in the series as per usual.


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What's the average age of an American convention attendee?
Where I live (Ireland), the convention scene is predominantly teenagers around 16/17. As I get older, I feel more out of place. I'm only 22, so I'm not old at all, but everyone else is so much more energetic and there aren't many people my age left. There are still attendees older than myself, but the number is usually in the single digits.
I watched Crunchyroll's livestream of an American convention (A-Kon maybe?), and it seemed to be a bit more diverse.
I've wanted to visit a larger convention on a visit sometime in the future, so I was wondering what the age demographic usually is for American conventions such as Anime Expo or Otakon.

I guess it really depends on the size and content of the expo. I'm not an American myself, but based on my European experience, is that expos that are held frequently attract mainly teenagers, unless they are held privately. Bigger expos, would attract teens and twentiers mainly, unless if they are mixed with western cartoons or scifi, that seems to attract a lot older audience, like thirties and forties. They wouldn't dress up though. So my bet would be to go to the most famous conventions and check out their pictures from last years to be sure.

I would probably agree with @PeterRaeves on this one. I am Australian but here at conventions such as Supernova there seems to be a lot of teenagers when I go mainly around the age of 14-16yrs and some under 12yrs since conventions here like Supernova, you can get in for free (if under the age of 12) otherwise you pay a fee which is about my pocket money every month. Lol.

All tough I don't know how this goes at the American conventions. If you look at the animecon in the Netherlands you will also see diversity depending on the time and size of the convention. As the convention is open 24/3 for the conventions duration. And there are also special events for 18+  people, such as speed dating.

I've been reading several articles and blog posts about this and I tweeted at a couple of the larger American conventions and one got back to me.
Otakon said that their main demographic is 18 to 28 year olds.
Anime Midwest is not as big as Otakon, but several places online mention the average age is about 17/18.
- "Anime-Midwest: Dear God, I'm Old"
Anime Boston seems to be reputed for hosting a young crowd.
A large-scale survey seems to indicate the average age for A-Kon in Dallas  is ~24
There seems to be a problem of fans graduating from anime fandom, so that the average age stays the same and cons sometimes face problems with disappointing turnouts because of the constant promotion drive.
Perhaps the larger cons attract older attendees as they might visit them instead of smaller cons because of more work commitments and etc.

I guess this is a vicious circle, where people that graduate don't want to hang out with a younger crowd as they grow older and move to bigger cons. I wonder what smaller cons could do, to break this circle though.

@PeterRaeves a couple of cons have enforced 18+ limits to boost older attendance, but they literally become 1/10th of the size for the effort

Might also be related to most modern anime settings being in high school or middle school.  When I was in college, that didn't feel weird.  Now that I'm old enough to have kids that age.... it feels weird, so I go out of my way to not watch school anime.

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Is Gekko Moriah human?
Obviously, Gekko Moriah is pretty funky looking.  I understand that his horns and wings are articles of clothing but his size, neck, and leek-like appearance are strange.  In a forum discussing fan theories concerning the nature of "minkmen" someone wrote that Oda confirmed Moriah to be a human (as opposed to fishman or snakeneck) and therefore "anything is possible".  I've been unable to find his source.
I am not asking if Moriah is a snakeneck or minkmen as I believe they have not yet been shown/identified by official sources.  What I am asking is: are there any official sources that identify whether Moriah is human?

Note: right now Minkmen are all shown to have hair similar to a specific mammal.  This seems to exclude that race.

I've yet to see an interview or article from Oda's words about Gekko Moriah concerning his race unless it was noted by Oda somewhere on the Japanese side of the fandom and it was overlooked and never translated...
However, the manga's latest arc is going to be dealing with Kaido, Moriah's greatest enemy, and I expect him to pop up soon. Hopefully, Oda will give us more detail on Moriah's background and make a side story explaining how exactly did his old crew get massacred (which I hope for cause I really wanna see Moriah back when he was young and badass.)

Well, after Donflamingo gets roasted by Law and the Strawhats first. XD

So the answer is that there is no currently known answer as I expected.  Excellent.  This answer will do nicely until things change.

This is all we know about him being a human :-

Moriah is a gargantuan person with very distinct devil-like features.
  Standing at 22' 7'' in height, he is the tallest among the
  Shichibukai. His animal theme is that of a gecko based off his name,
  general appearance and the collar of his shirt bearing a resemblance
  to a lizard's frilled neck. His overall design resembles a giant leek

Wiki Source

So as far as you know too, we don't know for certain what type of person he is from canon sources? (the wiki usually takes from canon but is itself not nessesarily accurate)

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What happen if the Supreme Kais were removed from Good Buu's body?
The fat version of Buu, or simply Innocent / Good Buu is the result of Kid Buu's absorption of Grand Supreme Kai and the Supreme Kais. Does the Supreme Kais still staying inside Good Buu's body?
I know if they remove the Supreme Kais, he will become the original Buu again. But, since the Good Buu and the Z Fighters were already removed from Super Buu's body, turning him into Kid Buu, then the Grand Supreme Kai and the Supreme Kais are definitely still inside Good Buu's body! But wait a second, if they remove the Supreme Kais from Good Buu, doesn't it mean that he will become Kid Buu again? Or he will split into the Supreme Kais and not having back the "Buu" body? Or, the Supreme Kais were just simply not exist inside Good Buu?

Remember that Fat Buu was removed from the Fusion/Super Buu. Both of the original Kais had long since been fully absorbed/consumed, and Fat Buu was the only thing left. Once Goku removed Fat Buu (also Supreme and Ultimate Kais), then Kid Buu (original) is what we are left with. If they had still been inside of Super Buu, then Goku/Vegetta would have seen them near Fat Buu.


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What are the characters that has their own unique abilities throughout the DB series?
There are quite a few characters that has their own unique abilities throughout the whole Dragon Ball series. Some of them are mostly forgotten due to their last appearance was on the original Dragon Ball.
Here's some example I can think of at the moment:

Fortuneteller Baba's employees (except Bandages the Mummy and Grandpa Gohan)
Ginyu - Body Change
Guldo - Time Freeze, temporarily stop time
Majin Buu - Change Beam / Chocolate Beam, change any object or person into sweets.
Ebifurya - Freezing Fist, freezes the victims.

I would also add:

General Blue - psychic abilities
Giran - Merry-Go-Round Gum (although it's stated that members of his race can use it)
Man-Wolf - turns into human during fullmoon

There are also other characters like Chiaotzu who can use telekinesis, but I'm sure there were some other characters that could do that as well.

Dabura - turn people into stone with spit
Hit - Tokitobashi (jumping backwards fractions of seconds in time) .
      Making ki clones
      Hiding in another dimension
Wiss - Turn back time
That fish fighter from the afterworld who changed the fighting scenario into water
The rabbit boss - turning people into carrots
Janemba - opening dimensional doors to hit you from anywhere

Probably a lot more


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Eighth gate of Gai
I know if you enter and use the eight gates formation that Guy Sensei used, you will die. So I was wondering, is there a way you can use it and won't die? Perhaps use it for a second or a really short time and get out? Or not even use, just enter it for showing? And also how does one know he can use the last gate?

The 8th Gate, also known as The Gate of Death (死門, Shimon), located at the heart, requires the user to stab their chest with their thumb to direct the chakra to the tenketsu. Once opened, the user will enter what's known as the Eight Gates Released Formation. Opening this gate will cause the user's blood to emanate a flaming aura of red steam, the so-called Steam of Blood (血の蒸気, Chi no Jōki) from all pores of their body, hair, and eyebrows. Releasing this gate uses up all of the body's energy while making the heart pump at maximum power. Exceeding the power of every other gate, the user is temporarily granted approximately a hundred times their normal power, far beyond that of the five Kage. Once activated, those who are capable can perform the Evening Elephant and the Night Guy. The side effect of opening this gate is that it comes at the expense of the user's life, causing the user to crumble to ash after their chakra runs out, having virtually cooked themselves from the inside-out. This is unlike opening the other gates, which simply injure or damage the body.
  (Source)

I don't think you can live after using the Eighth Gate because the Jutsu user has to thumb crush his heart and follow the blood from the user's heart directly.
I think to open the Eighth Gate you have to limit the overall flow of chakra within a person's body. The basis for the idea of the chakra gates comes from the body's limits on the functions within it. This makes the body much weaker, but it keeps the body from expiring too soon.

If any of this is directly quoted, you need to use the quotation markup (preface the line with a >)

can someone with extreme regeneration or healing technique use it? for example someone who can heal as fast as the eighth gate is destroying their body?(tsunade or sakura with their hundred seal or something)?

It is heavily implied that the User has no control over stopping what it does. How it kills you was never actually stated, but it is implied that the gate can not be closed and while open consumes chakra constantly. This is however an interpretation of what was shown, when

 Guy himself used the 8th gate against Madara Uchiha as the 10 tails jinchuriki. Upon piercing his heart with his thumb, he opened the 8th gate. Once he used his last attack, he was left in critical state and otherwise completely incapacitated, but it was also shown that his heart was still consuming the last little bit of chakra he had left. The other side effect also includes Literal incineration, As guy was practically on fire from the inside, and his blood was boiling. His final attack turned his toes to ash, and it looked almost like lava was coming out of his body.

It is also known that you die if you use all of your chakra, which has happened in the series, as shown when

 Kakashi died saving Choji in his fight against Pain. He exhausted all of his chakra to deal with the missile and died. It is also implied through dialog that Nagato also died due to chakra exhaustion, when he used Rinne art of Rebirth to revive Kakashi and the others he killed.

So, Its quite reasonable to assume that, since unlike the other gates, opening the 8th gate requires injuring yourself, there is no direct way to undo that action and close the gate. Since while it is open it seems to constantly consume chakra, and can't be closed, it will eventually consume all of it, which kills you. Later on, we find out

 there is a way to stop it. How it was stopped was not explained at all, but Naruto, who had obtained the Senjutsu of the Sage of Six paths, was able to use Yin-Yang release and somehow closed the gate, saving Guy's Life. Guy was permanently crippled already however, and Naruto could not heal that damage. So somehow, Naruto was able to heal guy, and undo the process that no other shinobi could undo.

So, Without some extreme circumstances, there is no way even remotely possible to turn it off. Activating the 8th gate is a death sentence, and the only clue as to how to turn it off requires the legendary abilities of the Sage of Six Paths himself.
So, pure speculation here based on the stuff in the spoilers, but

 Perhaps, if someone like Naruto, who obtained the Yin-Yang release healing abilities, also learned how to open the 8th gate, he might be able to activate it and then close it. The Yin-Yang healing based techniques Naruto acquired, at least temporarily, were capable of even creating a new regular eye for Kakashi when he lost his Sharingan one. However, the side effects of the 8th gate are severe, so even if only being activated for a short time, he would be temporarily crippled upon deactivation.

lastly, As for how they know they can activate it, it is not truly identified. All we know is that the main way is to pierce your heart with your thumb, which somehow activates it. Considering it kills you upon activation, the body would probably not let you do it. However, it is still just a gate, So it would make sense that it would work similarity to the other 7. Likely, something forcefully prevents the gate from opening, a seal of some kind. Piercing your heart could then either be destroying that seal, which causes the gate to open just as easily as any other gate, or it might physically destroy the gate itself, effectively opening it, but otherwise it cant close since it was destroyed. Since it is just a gate though, Its probably quite obvious to the user that something is blocking it from opening. Guy hinted that he might have found out how to do so from his father, and we know Lee knows how to do so since Guy revealed how its done. There may also be a scroll somewhere that teaches you how to do so, or at least up to the first 7 and records of what happened with the 8th gate.


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Do I need to catch up on anything before watching Dragon Ball Super?
I have watched most of Dragon Ball and Dragon Ball Z up to the culmination of the Frieza arc and bits of other DBZ episodes. I'm passively familiar with the overarching story line/details for some reason, but have not watched much Dragon Ball GT.
Do I need to catch up before jumping into Dragon Ball Super, or does the new show sufficiently explain things if you're not fully up to speed on the franchise?
I skimmed this stack exchange and did not see related questions.

DB and DBGT aren't necessary, but you should watch all the episode of DBZ before jumping into DBS.

Having watched every Dragon Ball Super episode as they came out, I would say that so long as you have watched at least Dragon Ball Z, you are good. Everything important in Dragon Ball is roughly glanced over or built upon in Dragon Ball Z; the same is true for Dragon Ball Super. Dragon Ball GT is officially not canon material thanks to Super, so it is completely unnecessary.
That being said, at least knowing everything that happened in Dragon Ball Z beyond the Frieza Arc is pretty important. There are numerous very important events that happened in the Android, Cell, and Buu arcs that are quite useful to understand what is going on in Super. The main story of Super is not based on those events though, because Super is about Gods. It will make it very confusing to understand a lot of what they talk about and do. It is not sufficiently explained. Many things can probably be inferred in some way, but I guarantee that almost everyone who is not caught up in Dragon Ball Z will either be confused or spending a lot of time on the wiki and YouTube watching clips, thanks to Super.


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What is the song's name of One Piece cap 717 min 15:02
I have been looking for the name of the song that appear in 15:02 on episode 717 when Kyros and Rebeca were reunited after the fight versus Diamante.

New World One Piece ost - the time of promise (dressrosa)
That's what i have found


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Who taught Tsunade her medical jutsu?
The greatest medical ninja should have learned it somewhere.

Tsunade's skills extend beyond the typical medical ninjutsu. She earned fame during the Second Shinobi World War for being the only person able to make antidotes for the poisons of Sunagakure's Chiyo. Similarly, she can make sleeping potions that are undetectable to even the most skilled ninja. She is knowledgeable enough to perform autopsies and examine damage on a cellular level.

Source from Narutopedia.

There's no background information explaining how Tsunade became a medical-nin or how she learned medical ninjutsu. She didn't have a medical specialist mentor. Maybe she did have one, but there's no source or background information to prove it.
There is a possibility that she learned medical ninjutsu all by herself, as she often read other clans' medical books to solve particular problems.

As others have answered that there is no concrete evidence on who taught her medical ninjutsu but we can theorize.
My guess would be the First Hokage. Consider the following information

He doted on his granddaughter and spent time with her to teach her gambling. (He'd said he shouldn't have taught her gambling)
He was the greatest ninja of his time. He could self "heal his wounds without weaving any hand signs"

Logically I'd guess Tsunade was influenced by the first and may have even got the basics of medical ninjutsu from the first Hokage. She then gained tremendous experience in the Ninja Wars and doing missions with the Sannin. The real life experience with the large amount of chakra and aptitude made her the greatest living medical-Nin in Narutoverse. She no doubt build on the initail knowledge travelling and reading about in other books, like Nara Clans Herbology.

I think she learnt it from Mito Uzumaki, The First Hokage's wife. She was the first to wield the Byakugou and was the second Kyuubi container. She could of had behind the scenes moments with Tsunade. Mito lived until Kushina came and collected the Kyuubi. Tsunade is like 20yrs older then Minato and Kushina so she still could have time to teach Tsunade how to unlock the Byakugou before she died.


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Why did Pariston Hill leave the election stage out of a sudden?
As I watched Hunter x Hunter on AnimaxTaiwan, I am not sure but probably Pariston won the election. Then he suddenly (probably) let Cheadle be the Chairman and left. If I am right, please explain his actions. If I am wrong, then please explain the election after the polls.

Pariston indeed won the election as Gon picked him because he knew Leorio afterall wanted to be a doctor. Also, take a look at the final result.

After that, Cheadle confronts Pariston in the hallway. These lines by Pariston might make you understand more about his action.

I didn't become vice chairman because I wanted to become chairman.
I just wanted to hinder the chairman.
When I said silly things to tease Netero, he always looked so happy...
I wanted to play with him some more.

After he wipes his tears off...

Cheadle-san, if the Association becomes a dull place under your leadership...
I'll get serious about toying with you next time.

He likes to play around and enjoy himself, of course on the election too. According to Ging Freecss, Pariston's personality is similar to Netero's and his own. He's still care about the Association, like in the lines saying if Cheadle makes the Association become dull and boring, he will really make fun of her. But, instead of becoming the chairman, he prefer be the vice chairman and make fun of the chairman to satisfy himself.

Well where did he go?

He becomes the vice chairman.

newest chapter revealed that, he quitting election stage out because he want to join the expedition to the new world


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How can Brook see and hear without organs?
How is it possible that his five senses are still working?
How can he even talk?

In short it is because of the Yomi Yomi no Mi Fruit's power he is able see, taste and do other things.
According to wiki:

Through the fruit's powers, Brook is able to function without the
  presence of necessary and vital body parts that have decomposed long
  ago. He is able to interact with the environment around him without
  the presence of eye balls or any other sensory organ to aid him. He,
  in particular, retains his ability of speech despite his vocal chords
  and even his windpipe have long since rotted away. He is able to taste
  and digest food like any other normal living thing to sustain himself.
  Drinking milk in particular heals him as the calcium intake repairs
  any of Brook's bones that may have been broken in battle. Depending on
  the situation, Brook is also able to produce organic matter such as
  tears, fecal matter, and even blood from his nose despite not having
  any organs nor bodily liquids to produce such matter.

In other words.....a character made to be creepy


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Is there a real version of "Understanding People's Feelings" series (the book series Sai reads)?
The character Sai, reads a book which has stuff like

The bond between 2 people increases when you give them a nickname.

And

When a woman feeds you, it is a clear sign that she likes you.

I want to read this book if it has a real version, or something close to it.

if you frequently hang around sites like 9gag there are post with things like that, so i think there has to be a book from someone who gathered all those and put them into a book. Try searching for a book on psychological lifehacks.

Sai reads many books. Therefore the sort of info he gains about people and interactions is not through a single source (in this case, a book). And most likely, the books shown in the series are just Naruto series exclusive. And mostly compiles of general facts about social interaction and bonding.

@EroSɘnnin "And mostly compiles of general facts about social interaction and bonding" so then Tsunade must really really like Jiraiya after feeding him that knuckle sandwitch that almost killed him

@Memor-X: like I said, general facts about social... Jiraiya's pervy nature called for that punch. Also, in the end, we find out that Tsunade did really like him a lot :)

No, the book Sai reads is to make the fact that he doesn't know anything about human emotions more pronounced. It's to also show the fact that he takes his position as being an information gatherer into play. He tests them on the field, and treats finding his emotions like a mission.

He’s reading a manga- as pointed out by Sakura in episode 72; the point is that the show Naruto is trying to help people (and other mangas) understand human emotion. Like literally watch the show/ read Naruto manga and understand that the show is getting across that we are all different and suffering and lonely and want to be acknowledged. Each character hints at different stereotypes of people and understanding them. There are books like what you are looking for but there is also a show called Naruto- think of the show as a life lesson and not an anime and you learn a lot about life


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How is Straight Tomoe Mangekyō Sharingan awakened? How is it superior to normal Mangekyō Sharingan?
In Naruto Shippuden, Madara tells Sasuke that he's so powerful because he could awaken a Straight Tomoe (Choku Tomoe) Mangekyō Sharingan. I wonder what is the difference between a Mangekyō Sharingan and a Straight Tomoe Mangekyō Sharingan and how is it more powerful than normal one?

The Choku-tomoe Mangekyō Sharingan is the completed transformation of the Mangekyō Sharingan, also known as Eternal Mangekyō Sharingan. Sasuke and Madara are the only known wielders that have achieved it throughout the series.
How to awaken the Straight/Choku Tomoe Mangekyō Sharingan a.k.a. the Eternal Mangekyō Sharingan

Transplant the eyes of the clan member to the user. In Madara's and Sasuke's case, they acquired the eyes from their brother, and both of them and their brothers already have Mangekyō Sharingan awakened. It's not sure that whether both donator and donor has to have Mangekyō Sharingan awakened in the first place in order to activate the Eternal Mangekyō Sharingan after the transplant. Although, it is not guaranteed to give everyone regained eyesight and ocular powers.

How is it superior to the normal Mangekyō Sharingan

It will usually regain the user eyesight. The straight tomoe of the Eternal Mangekyō Sharingan grants the user fluidity in the movements when fighting. It is suggested that the eyes can support non-Mangekyō ocular powers such as Izanagi and Izanami, when Sasuke asked his brother how they would use Izanagi to defeat Kabuto. You can find more abilities about the Eternal Mangekyō Sharingan here.

As far as I know from Madara and Sasuke's case, those who awaken EMS always have his eyesight restored. Also the name itself, Eternal suggest that this will always be the case. 2. The special MS specific jutsu such as Amaterasu and Tsukuyomi requires an MS, not EMS. As far as I know from be manga (canon), EMS offers no additional occular jutsu. 3. Izanagi and Izanami has nothing to do with EMS. Danzo sacrificed normal sharingan to activate Izanagi.

Upon using Mangekyou Sharingan, the user's eyesight will gradually gets worse. The more the frequency and the more strain the user puts on the eyes, the faster the process will be. Using Mangekyou Sharingan techniques such as Amaterasu, Tsukuyomi, and Susano'o puts great strain on the eyes, much much greater than just activating it. Thus, Mangekyou Sharingan will gradually lose its eyesight until it became completely blind. The evidences are:

Itachi was almost blind during his fight against Sasuke.
Sasuke was nearly blind after the fight against Danzo.
Madara said that he was pretty much blind when he transplanted his brother's eyes.

The Straight Tomoe Mangekyou Sharingan is a Mangekyou Sharingan that won't gradually lose its eyesight like a normal Mangekyou Sharingan. Thus, it is also known as the Eternal Mangekyou Sharingan. This is the biggest difference between the two.
Another difference between the two is that an Eternal Mangekyou Sharingan (henceforth EMS) is awakened by transplanting another's Sharingan. Throughout the canon (the manga) only Uchiha Madara and Uchiha Sasuke has achieved this. Both transplanted their brother's eye and both them and their brothers has already achieved Mangekyou Sharingan (MS) when the transplantation was done. An MS is awakened by watching the death of someone dear, which in Itachi's case was the death of his best friend, Uchiha Shisui. In Sasuke's case is the death of Itachi.
If I recall correctly Madara awakened his MS after the death of one of his brothers.
An EMS is not more powerful than an MS in term of power. It also doesn't unlock more occular jutsu. Upon acquiring EMS, Sasuke's Amaterasu didn't get any stronger. EMS only restores an MS' eyesight and removing its drawback of getting blind, which is why it is called Eternal.

Madara states that their bond may go deeper than blood, meaning he is aware of the possibility that Sasuke is his modern day reincarnate. He noticed that Sasuke has an Eternal Magenkyou Sharingan, something that Madara knew only he had accomplished. Is the Eternal Magenkyou Sharingan stronger? Yes. Very much so. Considering that with a regular Magenkyou Sharingan you can’t overuse the abilities before losing sight, falling ill, or wasting chakra, you cannot truly master or learn any of these abilities. Such as the perfect Suasnoo, the flame control techniques used in unison with Susanoo, and many other examples that have to do with MS specific abilities. The other strength behind EMS is it allows the user to have even better eyesight, and also allows for them to see in the dark as stated by Sasuke. Only Madara and Sasuke have truly accessed all of the fully developed versions of the base MS abilities because of their extended usage of their EMS.

An Eternal Mangekyo Sharingan uses less chakra. That's why it's more powerful because it can be used for a longer period than the Mangekyo Sharingan with the same level of chakra.


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Why does Major Armstrong sparkle?
I don't remember seeing any reasoning behind why Major Armstrong sparkles (although I've only ever seen the first anime series; I haven't read the manga nor seen the Brotherhood anime series).

Also, when we meet other members of his family, they also sparkle, if I remember correctly.
 And later on Breda even lampshades the sparkles, when he's cosplaying as Major Armstrong.

Was there any in-universe explanation ever given for Major Armstrong's sparkles?

It seems to me like the answer is just "because it's funny." Is there any reason you think there's a deeper reason?

Because I apparently had no idea there was a sparkles trope, as listed below!

CUZ HE'S FABULOUS

There is no in-universe reason for it, in the 2003 anime, the 2009 anime, or the manga. None of them give a reason for it, nor does any Word of God. In fact, Sig Curtis in Brotherhood sparkles a couple times as well, in addition to the rest of the family.
It's worth noting that there is a trope called "Bishie (bishōnen) Sparkle". I doubt many people would classify Armstrong as bishōnen, but that article does mention that it does represent the personality of the one who sparkles (as a bit of a cutesy "he's beautiful inside" fluff). Here's an excerpt from that very article:

In Fullmetal Alchemist, THE ART OF SPARKLING BEAUTY HAS BEEN PASSED DOWN IN THE ARMSTRONG LINE FOR GENERATIONS! And it really has, although Major Armstrong is more 'manly' than pretty.

It's not just Major Alex Louis Armstrong who has this trait, but THE ENTIRE ARMSTRONG FAMILY THROUGH THE GENERATIONS.
Not just the entire family: the sparkle is possessed by a flower woman whose family has SERVED THE ARMSTRONG LINE FOR GENERATIONS. And one of her hairs has the Armstrong curl, too.
Sig Curtis also develops a sparkle when he's doing manly things with Armstrong. Curiously enough, his sparkle isn't pink, but brown-ish.
May's Inner-Mind Theatre version of Edward and later Alphonse have this.
Roy Mustang gets some sparkles in the 13th episode of the 2003 anime adaptation during his duel with Edward.
As does Envy in the Chibi Wrap Party OVA, to hilarious effect.
Lampshaded by Breda when he's impersonating Armstrong to prank his colleagues: He's got small pink paper cutouts that look like Armstrong's sparkle, suspended on wires.
  Armstrong also sculpted a statue of himself in The Movie from the 2003 anime series; it had a small four-pointed piece of stone for a sparkle suspended by a strip of metal coming from the body.
Fullmetal Fantasy, the Fan Film produced by the English vocal cast, has Real Life Armstrong complete with sparkles, quite possibly the film's Crowning Moment of Funny.

Also, inarguably, it's funny. And the Rule of Funny applies.


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How did Goten and Trunks become Super Saiyan so easily?
Most Saiyan (Goku, Vegeta, Gohan, etc.) who evolved into Super Saiyan had trouble fulfilling one of the requirements to evolve: Their rage or other emotions had to be extreme.
However, there are two exceptions: Goten and Trunks (not the Trunks from the future). How did they achieve it? They hadn't seen or done anything that could drive them to such a level of rage/intense emotion to allow them to turn into Super Saiyan.

in the saiyan saga vegeta said, saiyan halfbreeds have power greater than purebloods because saiyans are trained to contain emotion

According to this Yahoo answer:

Because by the time they were born Goku and Vegeta had already been Super Saiyan and with the higher power level thus when trunks and goten where born their levels were also higher.
Think about it this way Vegeta (Fut Trunks timeline) was weaker at SSj Level so Future Trunks took longer to become ssj (i think he was 13) while Vegeta (regular DBz timeline) had trained harder by knowing the androids arrival 3 yrs prior to chibi trunks being born thus more powerful ssj1 vegeta. And Goten being born around some time near end of the Cell Games saga Goku had became already full power ssj.
Thus as children their power levels were already exponentially higher than the latter of gohan who was born back when goku was weaker in power level.

Basically Chi-Chi gave birth to a Demigod.

This has been addressed by Akira Toriyama in a 2017 interview, as stated in my answer.

the link towards @Chrygore's answer is here anime.stackexchange.com/questions/422/how-did-goten-and-trunks...#48901

Genetically speaking, Saiyans aren't human. So it's hard to say that by becoming Super Saiyans, Goku and Vegeta have altered the DNA in their sperm to be able to pass along those traits. I think the traits have been their all along, or maybe they are just traits that lay dormant in every Saiyan ultimately but most just never realize the potential.  Even though supposedly legend spoke of their being only one true Super Saiyan, every culture has it's lore.
That being said, children are definitely more susceptible to believing anything is possible. Goten and Trunks are brought into a universe different from the one their fathers grew up in. For them, Super Saiyans are no longer these "mythical beings" legends had everyone believe. Psychologically, achieving Super Sayian status was completely plausible in their young minds, and mentality did seem to carry a lot of weight in pushing Sayians to that super status. While it could be caused by anger or any other strong powerful emotion, for them it was just youthful passion for strength and an absence of doubt.

Actually, the "legend" apparently speaks of Broly.

I took that into consideration when i wrote this. 1. Legend is still just that, legend. Broly was only considered to be the legendary super Saiyan because of his immense strength at birth. 2. The movies aren't canon. Even if they were, apparently in the newest film, "Battle of the Gods", Goku achieves Saiyan God status. So there lies in my eyes the "legendary" Saiyan.

As a person who created a series as long as that, one would hope he put a lot of thought into it

He's really forgetful so I doubt even he knows why

This has been directly addressed by Akira Toriyama in an interview. Links to the translated interview can be found in this Kotaku article.
He addresses the case of Goten and Trunks here:

It's not like anyone can become a Super Saiyan through training and anger. In order to become a Super Saiyan, one's body must contain something called "S-Cells". Once these S-Cells reach a certain amount, a trigger such as anger will explosively increase the S-Cells and cause a change in the body: that's Super Saiyan. Most Saiyans have some S-Cells, although not a great quantity. The reason why Goku and Vegeta's children can become Super Saiyan relatively easily is probably because to a certain extent they inherited a lot of S-Cells, and also because Earth's environment is gentler and easier to live in than Planet Vegeta.

He goes on to say:

Having a gentle spirit is the best way to increase one's S-Cells, but most Saiyans have trouble with this, which I think is why no Super Saiyans appeared for such a long time and they became the stuff of legend. However, one can't reach the quantity necessary for becoming a Super Saiyan simply by having a gentle spirit, so a certain amount of battle power is indeed necessary. Looked at in this light, it's easy to see why becoming a Super Saiyan came easy for Goku.

So, it seems that having a gentle spirit along with a high power level increases the "S-Cells" in a Saiyan's body, and allows their children to become Super Saiyan more easily. This also explains why Goten was able to become a Super Saiyan even more easily than Gohan - when Goten was conceived, Goku's power level was far higher and he had already become a Super Saiyan. In the case of Gohan, Goku was far weaker at the time of conception.

I suppose that, since this is the Word of God answer, this is now the correct one (even if not the better explanation for this). Btw, when I read "S-cell" my first though was "Midi-chlorians"...

@BrianHellekin Oh I totally agree...I am not really a fan of this explanation myself, but it is the "correct" one (unless, of course, Akira Toriyama later retcons this in another interview...)

There doesn't seem to be an official reference, but I suppose there are three possible explanations (well, except the "the author wanted it this way" one):

Heritage: When they had them, their fathers already had managed to reach the SSJ stage. So they sort of passed the ability on and made it easier. This is true for Goku > Gohan > Goten and also for Vegeta > Trunks. This might mean that the base power level of their sons is higher than their.
Generations: The more you go on, the stronger they are. Gohan is stronger than Goku and Vegeta. He gets weak only because he doesn't train enough. Goten and Trunks are even stronger.
Blood purity: It is unclear, but it seems that hybrids are stronger than pure-blood Saiyans. Apparently, hybrids lack the will of combat these have, though. And indeed, Gohan doesn't train as much in peace time.

Well, it's a very late comment, but I can remember Vegeta saying that hybrids (human + saiya) are way more powerful than pure saiyans. So I think your theory no. 3 is the best: Trunks & Goten can turn easier into SSJ because they are hybrids. So why didn't turn Gohan into SSJ in the age of Trunks/Goten? Because ChiChi didn't wanted him to practice fighting.

A different view from what was already posted: because Saiyans get stronger the stronger their opponents are.
Goku, Vegeta and Gohan didn't fight Super Saiyan level opponents in their childhood. Gohan became a Super Saiyan while training with his father in the time chamber, and both Goten and Trunks trained with Gohan and Vegeta, who were already on Super Saiyan level at the time, so that could have made the kids gain more experience than their parents could.

They were born with there parents blood and got to train with there parents Trunks with Vegeta with the gravity ship and Goten with Gohan training together while he was also learning how to fly.

Also sorry not good at spelling characters names


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Why can't Pan go Super Saiyan?
As the title states, why can't Pan go to Super Saiyan Mode?
We see in the last episode of Pan's grandson turning Super Saiyan while he fights a descendant of Vegeta.  Are female Saiyans not able to turn Super Saiyan?

According to this wiki
pan never did have to go super saiyan mode.

[...] basically it's because the creator of Dragonball, Akira Toriyama claims that Pan never had a reason or situation to turn super saiyan. Her debut is at the end of dragonball z, as a little kid, and since Dragonball GT is not based off actual manga, Toriyama only envisioned Pan as a little girl in a time of peace, so there would be no reason for her to become super saiyan. Toriyama has also said that he doesnt exactly know how he would draw a female super-saiyan [...]

Well, according to this Pan's trivia section, the in-real-world reason seems to be that Akira Toriyama couldn't figure out how to draw a female SSJ.
One of the possible reasons, in the DB universe, is that Pan never really trained to become a more powerful warrior. The other kids, through the generations, managed to reach that level quite quickly yes, but they trained a lot too. Pan simply didn't feel that need that much.
The female SSJ appear in the videogames only.
Just for completeness, I discovered that according to an italian collection on the DB franchise, one of the fundamental requirements to become SSJ is to be a male. That would explain why Goku Jr and Vegeta Jr can still become SSJ regardless of the blood being diluted. This has been said across the internet, but there's nothing official about this.

Pan has never done any hard training in the Dragon Ball series. Pan may have her father's (Gohan) saiyan blood in her body, but she is not a full blooded saiyan like her grandfather (Goku). In Dragon Ball MMO (Online) the DB online game (created by Akira Toriyama), states that female saiyans are able to transform into a super saiyan.
In Dragon Ball GT Perfect Files, states that Pan would have a great potential to become a super saiyan. In the first ever canon Dragon Ball movie, Battle of Gods (that came out earlier this year in theaters in Japan), Shenron said, "there are 6 pure saiyans that were able to let Goku to transform into a Super Saiyan God form." These 6 saiyans are: Goku, Gohan, Vegeta, Trunks, Goten, and last but not least Pan (which of course Pan wasn't even born yet, and she still inside her mother's (Videl) stomach).
With the success of the brand new Dragon Ball movie, it's very unclear that there is a rumor about the new Dragon Ball series that was spreading across the internet this year. I don't know if that's true or not, but I hope will definitely see Pan turn into a super saiyan, a female super saiyan for the first time ever in Dragon Ball history.

As stated above, the main reason is Toriyama not knowing how to portray a female Super Saiyan, which might also be the reason while the entire offspring of both Goku and Vegeta until the very end of DBZ are exclusively male - and shown capable of transforming into Super Saiyans.
Since the potential seems to be passed down to the children, Bra and Pan both should be able to pull it off. Again, the question of design gets in the way, and the fact that until some point in GT when things began to go south rapidly, starting with Baby's using of the Ultimate Dragonballs, they lived fairly peaceful lives.
Also, bear in mind that all Saiyan-blooded children shown are halfbreeds or, in Pan's case, only 1/4th Saiyan. Taking Gohan as an example, the human blood inside him significantly dampened his drive to fight and the urge to train, which is why he preferred pursuing an education unlike his father and Vegeta who remain obsessed with improving their physical capabilities even in times of peace as if driven by instinct.
Since from the end of DBZ to the end of the first third of GT the Earth has been peaceful, halfblooded Trunks, Goten and Bra have had no reason whatsoever to train and lacked the drive to do so because circumstances allowed them to live peaceful lives. Pan only trained because of Goku and Mr. Satan's influence but seemed to take it more as a hobby.
In conclusion, given the right circumstances female Saiyans are all but impossible, except for the fact the species is nearly extinct.

I think it is because Pan, being female, was always in control of her emotions? Like most woman their emotions area what they can control. Unlike men who have a tendency to lose control and become angry as if it were a instinct. Take Goku, he transformed because of the fact that his best friend was killed therefore losing control of his anger. Vegeta transformed because he was angry that he couldn't surpass Goku and in the end just didn't care if he did. Goten transformed because his Mother (Chichi) kept picking on him through constant sparring sessions. Trunks transformed because of his Daddy issues, but whatever happened with Pan, she never got angry. She got upset but never ever lost control of what she was doing. Well that is my theory anyway.

Pan cries often in gt and behaves like a spoiled brat sometimes. Besides the issue of designing a ssj female, pan lived a peaceful life. She already had goku, Gohan, vegeta, gotenks, and trunks to protect her from the minimal  conflict of the times. Even the human females from Erath who were martial artists at some point stopped fighting to deal with family.  Not including 18.


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How could Piccolo blow up the moon, while Goku barely managed to leave a small crater?
In Dragonball Z, when Gohan changed into an Ozoro, Piccolo found an appropriate solution, destroy the moon. Easy-peasy.
The real question is, when Goku used his Genki Dama (on two occasions, by the way), it never resulted in anything more than a relatively small crater. With all the power stored inside that sphere (easy above a billion, and over 9000), shouldn't it have caused a bit more damage? Piccolo managed to destroy the moon, easily, with power level of less than 1000.

Is the title supposed to be metaphor?

@atlantiza At first I was confused lol

@Alenanno Me too. If it is a metaphor it might be best to change it. I clicked on the question because I didn't know Dragonball had dinosaurs.

@atlantiza Ah wait, Dragon Ball has dinosaurs. :D

@Alenanno Also to DragonBall z. (when Piccolo trained Gohan)

@HashiramaSenju I meant DB as a franchise. :P

@Alenanno This is a very sensitive and serious matter, You don't mess around with it. ;)

Piccolo isn't the only character to blow up the moon in Dragon Ball. Master Roshi (disguised as Jackie Chun) destroys the moon at the end of the 21st World Martial Arts Tournament using the MAX Power Kamehameha, which takes considerably more effort than for Piccolo. In the meantime, Kami recreated the moon, so this isn't a plot hole.
However, it's a good question as to why the moon is so easy to destroy, while the earth is so much harder. Part of this can be explained since the moon is much less massive, but even then the numbers don't quite add up if we assume the Earth and Moon are the same as ours. Let's assume that physics in the DB universe is at least somewhat similar to our own, modulo spirit attacks and whatever else. Of course, this assumption might be wrong, but if you start changing how physics works, there's no reason why the moon can't be filled with TNT so that it explodes whenever anyone so much as looks at it.
I've made some approximations in the following calculations. I calculated the gravitational binding energy of the moon to be 1.2 * 10^29 J. That's the minimum amount of energy to blow up the moon so that it won't reform by its own gravity, so we can assume that the characters were using at least that much energy. That amount would be enough to knock 3.4 * 10^20 kg of matter off of the surface of the earth, which is roughly 0.006% of the mass of the earth. That doesn't seem like a lot, but if we assume a uniform density of the earth, that's about 1.6 * 10^7 cubic miles of matter, which corresponds to a cube where each side has length 250 miles. That's a pretty huge crater. So just saying that the moon is easier to blow up than the earth isn't going to cut it.
There are 3 ways to resolve this. First, the earth and moon in the DB universe could be very different from what they are here. Specifically, the moon could be larger and less massive, and the earth smaller and more massive than in real life. However, it takes quite a bit of stretching to get believable values, and that's ignoring the vast power difference between DBZ Goku and DB Roshi. If you push things that far, I wouldn't expect it to be consistent with everything else in the series. The second possibility is that the moon is somehow more vulnerable than the Earth to attacks. This is roughly what Alenanno's answer says. It's entirely possible, but as far as I can tell there's little indication of this in the series apart from the Genki Dama, so I don't know why other attacks directed at planets would not destroy them.
This leaves the third possibility, which is my personal choice: the producers weren't really thinking about it when they did this, and were more concerned with making things dramatic than making them consistent. As such, I'd call this a plot hole, but it's a pretty minor one in the grand scheme of things.

I think option #3 is the most plausible. Thanks for your answer!

I take option 4, They did not want to blow up the planet with their attacks, so they learned how to contain the explosions. This would allow them to control the size of the destruction, and has the added bonus of condensing the damage to a smaller area, hence more of it to a humanoid target. After all, The same amount of energy over a larger area means less energy in the smaller area that is the target. This would also explain why small shots pierce (high energy in small area), and why punching is still valid (being efficiently contained in the fist)

Simple answer, Piccolo WANTED to destroy the moon. It has been demonstrated on numerous occasions that the characters in DBZ have a very exact control over their energy. The best option for how to look at it is that Goku when using the Spirit Bomb on Frieza didn't want to destroy Namek because it would kill him and his friends, the best explanation is that he concentrated the energy of the explosion almost entirely on Frieza. As for when it was used on Buu, at that point the bomb was not only concentrated on Buu but was also being fired at an angle (as evidenced by it pushing Buu backwards) so it can be assumed that the reason it only left a crater that time was because very little of the bomb's energy was focused on the planet. This is just my own speculation but if you wanted a reason then this would be your best one as trying to explain it in other ways leads towards more questions and even more speculation as to the powers of the characters.

Underrated answer, IMO. Self-control is a very important virtue that you would expect an expert (good or pure-hearted might be a requirement also) warrior to have (hence why it seems like every DBZ villain does great until they lose their cool). Therefore it's pretty reasonable to assume that both Goku and Piccolo (at least, post-Dragon Ball Piccolo) have fine enough control over their ki to decide whether or not they wanted to destroy the moon with a given attack. Of course that opens up a whole can of worms involving SSJ... but then again the Kaio-ken is a testament to Goku's self-control.

The Genki Dama (元気玉, Spiritual Energy Sphere) cannot be created by someone with an impure heart and mind. This implies that you use it against evil. It's positive energy that you use to get rid of the evil that is poisoning your world.
Still, this does not mean the Genki Dama is not powerful enough to destroy a planet. After all, King Kai says:

[...] If you can draw so much destructive power from a ball made on this small planet... ...Imagine what you can do with a Spirit Ball formed on Earth! If you can also learn to tap into the astounding powers of the Sun... Well. Just be careful. Or you may destroy the very planet you're trying to protect!"

So I suppose this means that Goku gets just the energy necessary to kill Frieza (or whoever was there) and not the planet itself. He's Goku after all, he supposedly can control his energy.
Piccolo doesn't have such a limit. He intentionally destroys the Moon with pure, mindless power.

Well, there is no physical evidence to that,
But Namek was approximately the size of Earth and the Moon probably was much more smaller.
so basically it was easier for Piccolo to do so.

You're forgetting Goku was about 1000 times stronger than Piccolo at that point.

According to TeamFourStar Dragon Ball Z Abridged youtube series, powerlevels are bullsh!t.

The simplest explanation I can think of is density.
Earth has an average density of 5.52 g/cm.
The moon has an average density of 3.34 g/cm.
So, it's possible that the difference is exponential - the difference may be only 2.18 g/cm, but the force needed to blow something up may increase from a (arbitrary numbers here) threshold of 100 (moon) to a threshold of 1000, instead of a threshold from 100 to, say, 300.

Goku was about 5-6 orders of magnitude stronger than Piccolo at that stage. I don't think that applies here :P


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Has the "It's over 9000!" meme spread back to Japan?
Has the "It's over 9000!" meme from DBZ spread back into Japan? Is it referenced in other manga or anime? If it is, do they use 9000 (which is, depending on who you ask, a translation error or an intentional mistranslation) or 8000?

As far as I can tell, it hasn't really spread back very much. However, my method of checking is a bit strange, so it's likely that a native Japanese speaker could answer this better. As you pointed out, the original version has 8000 rather than 9000. What Vegeta says in Japanese is "八千以上だ" which literally translates to "It's over 8000."
I looked on nico nico for any videos with "八千以上だ," but I didn't get any results. Removing "だ" gives some results, but none of them are related to DBZ as far as I can tell. I then tried all variations I could think of, like using "8千," "8000," writing 以上 in hiragana, etc. Still no DBZ videos. Using different versions of 9000 also doesn't get many results. A couple of videos that came up made some references to "9000千以上だ" in the description in such a way that they could be referencing the meme, but the number of these cases was pretty small.
I do get a reasonable number of results by searching "over 9000" on nico. All of these seem to be referencing the English version directly, i.e. they say "It's over 9000" rather than the Japanese version. So it does seem that there is some back-propagation of the meme, but they prefer to keep it in English. Also judging by the number of videos and the number of views on the videos, it seems it never became as popular as it did overseas. That probably shouldn't be surprising, given that DBZ ran from 1989-1996 in Japan and the meme only started in 2006, and mostly spread on English-language websites like 4chan and YTMND.

The Japanese version of this meme could be considered:
私の戦闘力は５３万です
My power level is 530,000
Which is close enough but didn't originate from the same scene. The joke also propagates to any score measurement in any setting. For example one can brag about their TOEIC (Test Of English for International Communications) score:
私のトーイックは５３万です
My TOEIC score is 530,000.
See https://dic.nicovideo.jp/a/530000 for more examples or just google the phrase.

That meme was started from the original DBZ but it got popular after TFS (Team Four Star) made a parody of the episode. And yes, it has mostly spread through Japan. But if you check, Nappa's power level was 4,000 and Vegeta was 2x more powerful, so Vegeta was still surprised. In conclusion, "It's over 9,000!" has spread to Japan.

As the post notice says, could you show any proof that "it has mostly spread through Japan"?


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Are there English dubbed anime on Crunchyroll?
It's of course understood that not all anime have been, nor will be dubbed.
Anyway, are there any English dubbed anime on Crunchyroll? If there are, is there a setting for it?

Crunchyroll has a small number of shows with English dubs. These are listed on their forums here. I could not find a way to search for them, so I have no way of knowing if the list is complete or not, but in any event there probably aren't a lot more than what is listed there. There have been others in the past, but never a huge number. CR is still primarily concerned with subtitled anime, which are typically cheaper and more abundant.
There are some other legal streaming sites which have larger collections of dubbed anime. What's available tends to vary significantly from country to country. In North America the biggest sources for legal dub streams are probably The Anime Network and Funimation. I unfortunately don't know whether these are available to the rest of the world or what the popular alternatives are in other places.

Funimation and The Anime Network aren't available in Ireland (and probably all of Europe) anyway, there aren't many alternatives either :(

@ToshinouKyouko These kind of streaming sites operate on US licensing. This kind of licensing is easier to obtain from the copyright holder and does not need to adhere to foreign rules. The European Union is working on governing laws that would allow licensing for the entire EU in one go. When, or if, that happens, more streaming sites will be able to reach the EU with relative ease. For now, there is no alternative for us (Other than, of course, the less legal methods of acquisition).


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When does One Piece take place?
When does the story of One Piece take place? Since the story is pirate-themed, I thought it may be at the time of the Golden Age of Piracy. The Golden Age of Piracy spans from 1650s to the 1730s. So I thought it happened around that time. Am I right or do they have their own timeline?

You had a pretty close guess there.

Using Noland's Log book as a guide, it is possible to work out that the current storyline of One Piece takes place in the sixteenth century with the Kaienreki reference.

A pretty accurate world time line has also been made on the One piece wiki although only updated till November last year ('13). For more info and their sources of the years mentioned you can check out their chat/change logs here

Well, actually! One Piece doesn't even take place on earth. It's pretty obvious when you take a glance at the planet's geography:

Not even during earth's theorized pangaea phase did it ever look like this. So One Piece is either very, very, very far into the future, or more likely simply not on earth at all.
A lot of ideas in OP are gathered from the eras you've mentioned, certainly, as a thematic thing, but they don't actually take place in those points of human history.

One Piece takes place in an alternate world and within an alternate timeline.
There is at least one calendar named Kaienreki. Noland Montblanc visits Jaya during Kaienreki 1120s. That being said to happen around 400 years before current time, we can say the main story happens during Kaienreki 15XXs

Ok, for one, no, it does not take place in the 19th century. It doesn't take place anywhere in time. Because coby wears modern converses, (which were made in 1949) and the witch refers to trash bags and toilet paper, trash bags were invented in 1950. And toilet paper was made in the early 19th century. So there is no actual answer to the question that you are asking.

I think it's far into the future on Earth and information about the past is misconstrued and only some things were carried on throughout the years like technological ideas, values, traditions, myths, phrases, etc. I also think that there was some sort of apocalypse hence the devil fruits, Giants, fishmen, angels on sky island, and the part about Cerberus during thriller bark.
The events leading up to the blank era were basically the rebuilding of humanity but much was forgotten after the apocalypse, and a group of people worked to recover that lost history and were successful. The government that was created soon after covered up those 100 years of revival because of fear that humanity would have to endure another apocalypse due to unknown reasons. The people who found out about the past before the apocalypse created the poneglyph to be indestructible using information found in the past in hopes of a full recovery for humanity.
My hunch also grew when Sanji asked Brooke if he ever heard of TMI, which is an acronym typically used in texting. Plus the Earth looks like it does due to geographical changes and the water between heaven and hell.

Is the scene about Sanji asked Brooke about TMI from the original Japanese/official English licensed, or from scanlation/fansub?

I believe it takes place during the 19th century, seeing as how the ships match up to those during the 1800s, the first gas operated stove was made during the 1820s and Sanji smokes cigarettes, which were invented in 1865 and mass produced across the world in 1881. This is saying IF one piece took place on Earth.

seeing as how the ships match up to those during the 1800s What did you base this on? Did you look at pictures? did you just guestimate this? Could you add some more clarification as to 'why' you think the ships match, and maybe some sourcing for the invention of cigaretes?

In Episode 184, one of the Shandorans says "What on Earth is going on? Those dark clouds..  What happened?"
It also doesn't hurt that the dirt is called Vearth.
Its the Hulu translation, so I don't know how correct this is...(https://i.sstatic.net/wW9fZ.jpg)

The question here asks for a when not a where ;)


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What does Captain Kurotsuchi do to Nemu in Bleach Episode 200?
What does Captain Kurotsuchi do to bring Nemu back to consciousness after her spirit particles have been absorbed by Szayelaporro?
I remember Ishida saying that it couldn't be aired. what exactly did he do?
You can watch the scene here.

The manga doesn't explicitly state what Mayuri did, and Uryuu makes the same remark.

However, it seems very likely that Mayuri fiddled with Nemu's "reset button"1, based on her moaning (see screenshot below), and his remark:

You can't even understand something that simple by looking at it?

He later derides Uryuu and Renji for reaching wrong conclusions, and calls them laymen who do not understand his technology. This suggests that he might have given Nemu something like a Tantric Massage. Laymen watching it in our world would reach exactly the same wrong conclusion.

I know the above theory is a speculation, but this is as much evidence I can provide to support it. I guess we won't know any more of what he did for the reason Uryuu mentions.

1 Sorry, I cannot be more explicit than that. I hope you know what I mean.


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How does Goku's hair grow longer when he becomes Super Saiyan 3?
TIL Super Saiyan 2 Goku's hair is the same length of his normal hair, but when he transforms into SSJ3, his hair starts growing and becomes pretty long.
Even if the hair grows while in SSJ3, it should not shrink back when he's returns to normal. The growth could be the result of the pressure exerted from his body, but shouldn't shrink back when he's normal.
Is there an explanation for that or is it just the way it is?

Just a thought. It might be something similar to this. Just like the color of the hair changes when Goku goes from normal to SSJ and vice versa, the length of the hair too changes when transforming between different levels of SSJ and the normal self. Another example would be of DB GT, where Goku is a kid and when he goes to SSJ4, he becomes tall and his hair grows, but when he returns to normal, he gets back his kid size again.

well one could say that the extra hair comes from their eyebrows since i remember not seeing any in Super Saiyan 3, maybe it also gets pulled from other places like their back, chest and legs....then again i don't remember seeing Goku have hairy legs to begin with

@R.J I overlooked SSJ4 because it was a filler.

Well the whole DB-GT was not exactly a filler as Akira Toriyama oversaw the production of it. Nevertheless, the point there was that, transformation changes the physical characteristics of the person, and when transformed back, it only makes sense, to go back to normal. Though, there can't be a definite answer to this, as it was not mentioned by anybody, why such changes happen during transformation. If the answer for one could be found, we could use it for others as well.

It's just a design decision, there's no deeper meaning to it than "because it looks cool".

If Saiyans can go great ape & revert back without question, then condensed transformations like SSJ can follow the same principle. Think of it like overclocking your cellular structure, revving up a car engine, or puberty.

How do they increase and decrease their muscle in instant, or how he loses his eyebrows and how he recovers them? How do Oolong and Puar change into things, Krillin sneezes without nose, or how Goku flies waving his tail as an helicopter? Dragonball is not scifi, and you cannot explain many things that are done just for fun or awesomeness.

Again, if we think of Vegita's theory of hair, true saiyans hair does not grow, they are fixed when saiyans are born.. but this theory conflicts with SSJ transformation

Before we begin an answer:
I prefer honestly saying that there is no answer for this (or I personally never saw something that answers that on the web), but we can use some deductions from what we know and experienced from the long series of the anime.
As we already know from Dragon Ball, the trademark characteristic of the transformation is the user's hair, it goes golden yellow at the Super Saiyan 2 level as a representation of achieving a higher level of energy.
I guess you could also ask:
why does his hair goes golden yellow at the first place ?
For me I know no reason of getting hair color changed when rising the energetic level, but by assuming that saiyans are a different race than humans, we could explain it as a result of the rise in Ki consumption, for example in SS3 :

The rigid hair of the Super Saiyan 2 state becomes flowing and smooth again, and grows down to or sometimes passes the user's waist. The eyebrows vanish completely, making the forehead and eye ridges appear larger and revealing a more prominent brow ridge. A small increase in muscle mass is evident, and muscle tone is sharply defined. Energy radiation is so great that the aura pulses at an extremely high frequency, almost to the point where it seems static; the sound of the aura is also pitched even higher than that of Super Saiyan 2. Bio-electricity, like in the Super Saiyan 2 form, is again constant, and may reach further outward from the body than before. The Saiyan's voice may become slightly deeper, though this is obviously a feature only found in the anime. If the user of the Super Saiyan 3 form has a tail, it turns yellowish gold.

Source
So as a personal explanation:
I can say that just like when you eat a lot you get fat (as a human), when you open your body for a perfect Ki consumption (as in SS3 level) your hair will grow as long golden yellow (as a Saiyan).
And as a remark:
The body must change the morphological shape to achieve a higher efficiency in using the current level of energy for combat (for example largest muscles in SS3, tallest in SS4 .. etc), and as one can deduce: hair has no effect on the combat course, but personally again, I think the complete opposite: the hair style may cause more effect than muscles, it have an impact on the moral and psychic state of the enemy, to make it even clear:
Just like the lion is scary with large hair, so is the saiyan in SS3, he looks stronger sometimes more than what he really is. Unlike what was the small evil Boo, his physical appearance didn't show his strength therefore it had no impact on his enemies (Goku and Vegeta).

I have to say that the bulleted answer that I just read was incredible, and a lot can be taken away from that to understand the Saiyan race.
In my eyes, the Saiyan's hair is a very key part of their ki control, their physical stature, and their own understanding of themselves. I believe it was Vegeta who said to Bulma that a Saiyan's hair never grows, it never changes (to paraphrase, of course).
Saiyan's hairstyles and strengths
It does not seem that the length of a Saiyan's hair is immediately related to the base power of the Saiyan. The Saiyan saga made it quite clear that Raditz is weaker than Nappa is weaker than Vegeta, and the lengths of hair do not grow shorter or longer in that sequence, as Nappa is bald and is stronger than Raditz (according to Team Four Star, Nappa is 5Raditz, lol). It's possible that I'm wrong, and Raditz had unrealized potential to be unrelentingly strong but was too mentally weak to achieve it. However, I don't believe this to be the case.
Supers and their hair
Now onto the relationship between the hairstyle and Super Saiyan abilities. To make a note, all the Saiyans we know to have achieved a true Super Saiyan form, had hair. This is minor, but makes the analysis a whole lot easier. Goku and Bardock were the first two Saiyans in known history to transform and they had the same fairly short, spiky hairstyle. Vegeta's early SS form was a bit invalid in my opinion, as he forced his way in, like achieving full meditation with help from drugs. However, his hairstyle is in many ways very similar to Goku's, which I will comment on in my next point. Goten, same hairstyle as Bardock and Goku, and as far as Trunks, that's just a different story, I'll make a side point in the end for that.
Goku vs. Vegeta
So what is the difference between Goku's hairstyle and Vegeta's (in base form)? If you look closely, their hairs are actually quite identical. I've never counted the spikes, however. If Goku's hair was forced upward I feel that they would be the same length and style. This opens up to my real idea of what the hair represents. On Earth, martial artists have the ability to suppress their power, not hide, but suppress. Vegeta learns this, proving he never had this ability before coming to Earth. So while Goku spent his life only bursting his power at the moment he needs it, Vegeta has always pushed himself to the limits at all time. I believe their hairstyles resemble this. Goku is always at peace and relaxed, so I believe his hair is relaxed and does not flow as much ki. When Goku uses the Kaio-ken, his hair rushes up for just a moment.
A channel for ki
So all in all, my theory is that a Saiyan's hair has no cosmetic value, and is a direct representation of their average ki consumption. When Goku and Vegeta transform, their hair is passing far more ki than normal, and this causes it to stand up and resemble their aura. For all known Super Saiyans, there is a gold aura, however we do not know that this is always the case. Perhaps the SS of legends, thousands of years ago, had a green or red aura. However, Goku and Bardock have a golden spirit aura and Vegeta learned to transform by watching Goku, resembling his technique and passing it to his son Trunks (again, not getting into that little bastard). Broly's final transformation had more of a green aura as well, but I'm not an expert on the movies.
SSJ1-SSJ2-SSJ3
The typical first transformation involves the hair turning from black to gold, and the eyes turning bluish-green. The next transformation involves the hair to flow even more forcefully upward, the aura to grow sometimes with lightning, and muscle growth. Then the transformation to SSJ3, which I have only seen done by Goku in the greatest scene ever, involves the obvious growth of hair, more muscle growth, and some major facial changes.
SSJ3 analysis
Now I think I'll get to my opinion on the question that was asked. In the SSJ3 form, not only do the eyebrows disappear, but the entire forehead grows severely. It seems to me that the top of the head and base of the hair is the last biological point in the body which passes ki, and the growth of his cranium is no doubt to accommodate the intense flow of ki. The eyebrows may serve as an auxiliary port for key to enhance vision and the senses, or even just to project ki in different directions. However, when the body must focus enough energy to reach such a high level, such accessories are pointless, therefore they vanish into the flow of ki. When I watch Goku transform for the first time on Earth, I see him not only intensify his own energy, but taking it in from the world, like a slowly expanding spirit bomb in a way. The clouds fly towards him, the grasses bend his way and all the trees shake immensely. His body is at that point holding far too much energy to handle and he must adapt his physical body to survive and use that energy. This is where the hair reacts and becomes much larger to allow him to hold the energy a little longer and direct his power much more finely. This doesn't answer the question how hair could just grow and shrink, but the idea is, maybe instead of calcium and proteins, a Saiyan's hair is made of raw ki.
Trunks
I promised to make a side note on how Trunks' hair works, so here it is. Trunks can go screw because I don't want to think about the one hole in my entire theory. Bulma is ruining it YET AGAIN and I'm sick of her s**t. SICK OF IT!

Maybe it is because a saiyan's eyebrows disappear due to the increase of muscle around the eyes, there for increasing their sight ability furthermore.
The hair length though. I'd say it's half cosmetic just for intimidating purposes but also because it has a deeper meaning. The hair styles with saiyan's personally, going off human hair, means nothing. But the increase of hair length of a Saiyan hair being that it increases in length through base form - SSJ3 (yes it does increase slightly). This maybe a way of cooling the body down or an outlet for excess energy that the body needs to exile or does naturally. I don't believe it to be an energy channeler as there isn't any evidence and it make no sense, but that's clearly my opinion.
As to the original question as to why the hair increases and why this change is not permanent maybe due to the fact that the body undergoes mass physical changes to adapt to the physical and physiological needs to the present form, or even just a simple side effect of the transformation in which the changing of the hair could all just be a coincidence and an unintentional argumentation.
When the user "retreats" (and I use that term loosely) the side effects or the augmentations due to the transformation are reversed due to the transformation "retreating" and no longer in effect.
I.e. Like when a smoker starts after a while their lungs get worse but as they start to quit, their lungs become better. Same theory applies. Not being in that state returns the body back to its original form.
Hope that solves your question and others as well, I hope someone finds my theory to be interesting.

This isn't an answer, but rather a theory:
Just like when your hair becomes charged from static buildup and begins to rise, when a Saiyan goes Super Saiyan, their hair becomes super charged with Ki energy to such an extent that it literally begins to glow, resulting in a blond appearance.
As this charge is pushed to greater extents, the focused charge pulsing from root to tip not only glows outward from the shaft, but also fires a visible laser like beam of light from the tip, resulting in the apparent lengthening of the hair.
As this charge is pushed to EVEN greater extents, the visible distance of this light is amplified, and the space around the hair begins to distort, further "lengthening" the hair, as well as amplifying it's volume.


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Who controls the mind after fusion in DBZ?
In Dragon Ball Z, after fusion, who controls the mind and the body? Is it both or a single person?

There are several types of fusion. For the majority of these, the more dominant/stronger individual controls the mind and body.
For Piccolo and Nail, they did the Namekian Fusion, Piccolo was the more dominant. There was also Cell and the Androids. Cell fused with them by a type of fusion called Absorption. There was also the permanent fusion of Supreme Kai and his servant Kibito by using The Potara Earrings. Supreme Kai's personality was the one that stood out after that. For Dragon Ball Super we also see Kale and Caulifla fuse into Kefla who actually only seems to inherit Caulifla's personality.
In the normal fusion, the one you are more than likely asking about, the one that comes after initiating the Fusion Dance. A new being is created from both individuals. This being will..

combine both their attributes, from strength and speed to reflexes, intelligence and wisdom. When properly fused, the single being created has an astounding level of power, far beyond what either fusees would have had individually.

So, none of the fusees control the mind after the normal fusion. The being created after is a combination of both of their individual attributes and as such can think for itself.

Combing with the Potara earings will yield a similar result, in terms of personality, as with the fusion dance

So who controls the body of GOTENKS?

@HariNandha Read the answer again. Gotenks is a completely different individual created from both of them. So, neither Trunks nor Gohan does.

@iKlsR You mean Goten, not Gohan. ;)

for the fusion dance, you can add that up to five people can fuse at once that way, so the new being is more adequate than a "dominant personality"

@gl_prout source?

You meant Kefura inherited Caulifla personality? Kale is shy, Caulifla and Kefura are carefree

@Pablo right, got them confused.

@iKlsR I can't recall correctly but I think it was explained by Goku when he was teaching it to the kids

@iKlsR it's even stated in the link in your answer that "More than two people can perform the fusion dance", just before the "God fusion" title

It's a totally different person, e.g. x + y = z.
So it's not either one. Once they are fused, a new superpower being is formed.
If you remember what Trunks says to Pam when Goku and Vegeta are fused, he'll say that they both are not two different entity. They are one being :)

Welcome to Anime&Manga! Please consider editing your answer to include some more details, namely some sources for your info. Happy answering~

Fusion dance = an entirely new being. And as far as the earrings go, it depends.
If one person is far more dominant in power and personality, then they remain who they are and are in complete control of the new form (old Kai and Kabito Kai), but if both fusee's are equal in power and dominance of personality, then similar to the dance, a new being completely will be created. You can tell if this occurs if you can hear both fusee's voices (Vegito).

No one, once fused. He or she is an entirely different person, with a brand new personality and everything.
An exception would be the Namekian fusion.


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What is the purpose served by cicadas in anime?
Why do so many anime (e.g. Code Geass, Steins; Gate, Ano Hana) have cicadas in the background?

Read more about it here, yes it is a cultural gap for Western audiences (WARNING TVTROPES): http://tvtropes.org/pmwiki/pmwiki.php/Main/CicadianRhythm

@congusbongus: not to be confused with Circadian Rhythm.

In Japan, cicadas are symbolic of summer, and possibly symbolize reincarnation as well, based on summer being the time when the cicada comes out to sing.[1]

As per their role in anime, according to Wikipedia,

The songs of the cicada are often used in Japanese film and television to indicate the scene is taking place in the summer.
  — Cicada, Wikipedia

I do not remember when exactly they appeared in Steins;Gate (nor the other anime), but I would assume that this is simply a reference to a summertime setting.

I'm curious how this is reflected in Higurashi no Naku Koro ni, where it literally is "When the cicadas cry", and if that has any bearing on your answer.

@Seiyria A live action film adaptation of the series entitled Higurashi no Naku Koro ni (ひぐらしのなく頃に, also known as Shrill Cries of Summer internationally), directed by Ataru Oikawa, premiered in Japanese theaters on May 10, 2008.

@Seiyria ひぐらし is a particular species of cicadas, and they may have additional connotations.  They usually start crying in the  evening, so I suspect many people associate them with summer evenings.  Moreover, in literature, they are symbols of late summer or autumn.

I grew up in an area that was close to sea level (a bit further south than Japan) and in the Spring and Summer I recall hearing cicadas just about every time I went outside.  I suspect the effect in anime is to improve immersion or accurately reflect the reality of the situation that the anime is trying to portray.

Thanks, I wondered if Cicadas ever chirp in sunshine, as in Steins Gate. Do they even chirp inside cities?

@aitchnyu They made noise whenever it was hot (85F and higher).  I've heard them day and night.  Consult the wiki linked in the top answer.  [Wikipedia]http://en.wikipedia.org/wiki/Cicada#Cicada_song


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Why didn't Sarutobi kill Danzo?
As I'm watching these filler episodes, I am wondering, why was Danzo still alive, after doing all the things he did to The Third? He hid a Wood style user, he tried to assassinate Sarutobi (not even once), he tried to lure the Anbu forces to join the Federation, he tried to manipulate the Hokage election after the death of Minato, and so on (just from these couple of episodes, without mentioning the whole "rivalry" between them).
The Third was aware of the situations, since he warned Danzo a lot of times. So even if he was a member of the Hokage's council, why did Sarutobi endure the disrespect and danger that came from Danzo? I would've been pleased even with a ban from the Village, but given what he had done, Sarutobi could've eliminated Danzo without any efforts.

Danzo was, in his own way, protecting the Hidden Leaf.
Danzo would normally do the "dirty work" and handle with that "black ops" of the Hidden Leaf, thus keeping the village officials clean.
They had their disagreements, and yes Danzo did act in order to dispose of the Third and have control over the Hidden Leaf, but Hiruzen always believed that all he's doing was for the best of the village, so he let it slide.

also hiruzen is shown to have a very soft side. Even after he found out the evil doings of Orochimaru, he did not attempt to kill him.

@debal - That was more because Orochimaru was his student and he couldn't come to terms on killing his own student. The softness part only had a little effect in this specific case.

@RJ and Danzo was his team mate

but then we can safely assume, that in the end, practically Danzo caused Sarutobi's end..

Sarutobi is a very uderstanding man, he probably just figured he'd give Danzo the benifit of a doubt, thinking that age would give him wisdom and he'd see that he was wrong,
too bad that never happened

Danzo had Shisui's Kotoamatsukami. He also had Hashirama's cells, which enabled him to use the jutsu to his advantage with regeneration. So there is a possibility that even if Hiruzen wanted to kill him, Danzo could have used Kotoamatsukami to manipulate the Third's thoughts about him.

i doubt God of shinobi who lead countless uchiha can be manipulated by non uchiha sharingan user.

@NamikazeSheena huh? What does being an Uchiha have anything to do with it? Danzo was in Sarutobi's close circle. Plus, he had access to multiple Sharingan and had above average knowledge about them. Thats power. And about manipulated by non uchiha .., Kotoamatsukami isnt your everyday manipulation trick.


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Is there any meaning behind Zoro's headband?
When Zoro gets serious, he always wear his headband. Where did he get that? How did it become so important to him? Is there any back story about it (Maybe from a movie or something)?

http://en.wikipedia.org/wiki/Hachimaki , in particular: worn as a symbol of perseverance, effort, and/or courage by the wearer.

I think that the answer is Kuina. When things get serious, he wears this deep blue bandana because he feels that he is fighting with kuina together. The hair of Kuina is deep blue, so that's another hint. If you remember, Zoro and Kuina promised to each other that one of them will be the greatest swordman. What do you think about this?

There isn't any meaning or any special scene related to his headband.
According to the Wiki :-

Zoro normally keeps a black bandanna tied around his left bicep and
  ties it around his head when he is fighting seriously against an
  opponent.

Atleast till now, nothing has been revealed about his headband. If it resembles something important, Oda Sensei will mention something about it in the future.
For now, we could just consider it as his style of dressing.

Even though it is not officially stated yet I love to believe this is to make his hair look black like Kuina's. He also wears a white shirt like she used to do so ah well :)

after time skip he doesn't wear white shirt. I love to believe that it is some keepsake from kuina or Something like the armband he wore during kuina's funeral.


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What is the meaning of the word Kamehameha?
In Wikipedia, Kamehameha is defined as a species of butterfly.

kamehameha
  Web definitions
  The Kamehameha butterfly is one of the two species of butterfly native to Hawaii. The Hawaiian name is pulelehua. ...
  http://en.wikipedia.org/wiki/Kamehameha_(butterfly)

What does it mean in the Dragon Ball series?

Japanese Wikipedia claims the following: "The name originated from King Kamehameha of Hawaii. When Toriyama was coming with move names, his wife, MIKA Minachi, suggested it, and Toriyama agree, saying 'It was quite silly, and thus suitable for Master Roshi.'" Of course, there is probably also a pun involving "turtle" (亀, kame, cf. Kame-sennin = Master Roshi) and "wave" (波, ha [the second one]).

According to Dragon Ball Wikia:

Akira Toriyama actually tried a number of poses when he was alone in
  order to decide the coolest pose for the Kamehameha. After much
  contemplation, he could not decide on a name for his "Kame" attack, so
  he asked his wife who came up with the name. She told Akira that it
  would be easy to remember the name of the attack if he uses the name
  of the cultural Hawaiian king named Kamehameha (lit. "the very lonely
  one" or "the one set apart" in Hawaiian language). Also, Kamehameha
  means "Turtle Destruction Wave" in Japanese.

So, despite the literal translation in Japanese "Turtle Destruction Wave", Kamehameha is also a name of a Hawaiian king:

Kamehameha I (Hawaiian pronunciation: [kəmehəˈmɛhə]; c. 1758 – May 8,
  1819), also known as Kamehameha the Great, conquered the Hawaiian
  Islands and formally established the Kingdom of Hawaiʻi in 1810. By
  developing alliances with the major Pacific colonial powers,
  Kamehameha preserved Hawaiʻi's independence under his rule. Kamehameha
  is remembered for the Kānāwai Māmalahoe, the "Law of the Splintered
  Paddle", which protects human rights of non-combatants in times of
  battle. Kamehameha's full Hawaiian name is Kalani Paiʻea Wohi o
  Kaleikini Kealiʻikui Kamehameha o ʻIolani i Kaiwikapu kauʻi Ka
  Liholiho Kūnuiākea.

About the best source I can find on the matter indicates that it means "Turtle Destruction Wave".  But I can't derive that from the provided hiragana alone.
It makes sense if you break it down:

Turtle = Kame = 亀
Wave = Ha/Nami = 波

...which is essentially "turtle _ wave", which is a nod to Master Roshi (the Turtle Hermit).
If I fiddle a bit in Google Translate, I get something closer to 亀羽目波, which is literally "turtle wind-up wave" - and that sounds close phonetically.

I think that the "Turtle Destruction Wave" explanation is something that somebody on the internet just invented, and everybody just believed that person for whatever reason. There isn't any Japanese I'm aware of that supports hame -> "destruction"

The best explanation I can find for はめ being translated as "destruction" is that it's a shortening of はめつ. While not completely impossible, I don't find it very convincing since there don't seem to be any official sources backing this and linguistically it's a pretty big stretch.

亀     Kame        Turtle
破滅   Hame(tsu)   Destruction, Ruin
波     Ha, Nami    Wave

Turtle for Roshi's Turtle school. (It's the kanji on all their gi) Then hame and ha for what the ability is. (A destruction wave.)

The term Kamehameha seems to come from the king of Hawaii, King Kamehameha. However this is not the case: Kamehameha is a term for something along the lines of "Turtle Destruction Wave", or のカメの破壊の波 (No kame no hakai no nam). That is as close as I could possibly get it to Kamehameha, which is what Kamehameha stands for: Turtle ____ Wave. But because it destroys anything in its path, I would assume that it would be "Turtle Destruction Wave".

Japanese Wikipedia says it comes from the Hawaiian king, recommended by the creator's wife. The "kame" part is a bit of a pun because it can also mean turtle. "Hame" has no meaning. "Ha" means wave.  On the whole, it just sounds a bit silly, which is on purpose. "Turtle destruction wave" is fake news and there is absolutely zero support for that interpretation. 破滅（はめつ）would never in 100 years be abbreviated "hame" in Japanese. Source: Japanese speaker.


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Do Bardock and King Vegeta make appearances in Otherworld?
This is a two part question:

If Bardock and King Vegeta are dead, do they ever make appearances in HFIL or Upper World? One would think that either Goku or Vegeta would want to pay their fathers a visit.
Do Goku or Vegeta ever mention their fathers once during the entire anime?

I don't recall any of this. Feel free to include the manga if anyone has that much knowledge on the matter.

I don't remember about Goku or Vegeta, but Raditz definitely mentions Bardock. He says something about Goku looking like their father.

I don't think Goku knew that much about his father, growing up with his grandfather since he was young

Yeah but that's what I'm saying, Goku called him Grandpa Gohan, implying he knew it wasn't his father, so he never thought to question this at one point

@userFace Goku called Gohan "Grandpa" because that's what Gohan told him he was. AFAIK, Goku never gave a thought about who his father was. He isn't the most philosophical reflexive guy, you know.

Anime and GT series make a lot of confusion with its fillers, but in the manga, Piccolo explains water-clear to Vegeta.
Evil souls are cleaned, their memories wiped, and then reincarnated.
Both King Vegeta and Bardock, although heroic, are clearly evil, so they are impossible to visit.
Goku never shows interest for knowing about his father. He was raised by humans, and he consider his adoptive grandfather as his true ancestor.
Please, also notice that HFIL is an invention of the American dub, which you should avoid if you are really interested in Dragonball canon. Where Goku goes is called the Other World, and what is written on the otherworld's demons' shirts is "HELL".

Yes there is an episode where vegeta has a dream about his father telling him about his royal blood an sayian ancestors.. Also I think there's an episode where bardock has a vision of goku defeating frieza but I dont think goku ever mentioned anything about his father I do remember vegeta telling goku something about his father bardock said he wasn't the best fighter but a brilliant scientist

Can you cite the episode numbers?