How did Asuna and Kirito survive?


In the last episode of Aincrad arc of Sword Art Online, how did Asuna survive
even though her avatar disintegrated after being attacked by Kayaba? Also
Kirito was stabbed by Kayaba as well. How did he survive?

Was it in the novel on how they really survived?




> Divine Stone of Returning Soul (還魂【かんこん】の聖晶石【せいしょうせき】, Kankon no Seishōseki)
> is a unique rare item found in «Sword Art Online» that can be used to revive
> a recently fallen player. The only known way to obtain it was to defeat
> Nicholas The Renegade, the Christmas event boss, during the Christmas Event.

![Divine Stone of Returning Soul](https://i.stack.imgur.com/4bwSi.png)

_Item description and image source:[Sword Art
Wiki](http://swordartonline.wikia.com/wiki/Divine_Stone_of_Returning_Soul)_

I remembered this item was mentioned to have existed within Sword Art Online
and that it was hypothesized that it must obey the laws of the game. Part of
the reason for the delay between a player dying within the game and being
killed by their Nerve Gear in real life, was because there is a chance for
them to be revived within the game. To me this explains why Asuna was able to
live, because the world was 'saved' very soon after her avatar's HP hit zero.

While this could explain why Kirito didn't immediately die after his HP was
zero, it doesn't explain why his avatar was still able to last hit the world
boss after receiving a death blow. I have a hypothesis for this, but this one
is even a larger leap. In Sword Art Online, there are skills known as _Unique
Skills_ which are rewarded to players who satisfy certain conditions. Kirito
had the Dual Swords skill (rewarded to the player with the fastest reaction
time). My hypothesis is that this unique skill could also have a "last stand"
or "last resort" type of skill to get that last hit in or increase DPS for the
user in their final throws which makes sense for a player with the quickest
reaction time in the game.

Another possibility is that Kirito could have earned more than one unique
skill which allowed for his final thrust. The creator of the game stated that
there are 10 unique skills and each one is awarded to the player who satisfies
the condition best in all of SAO. He stated that the 10 unique skills are
awarded to only one player each, but did not say that a single player couldn't
obtain more than one unique skill. Out of the 10 unique skills we know of
these six:

  * «Dual Blades» - given to the player with the fastest reaction time
  * «Holy Sword» - given to the strongest player.
  * «Darkness Blade» (暗黒剣, Ankoku Ken)
  * «Battoujutsu» (抜刀術, lit. "The art of drawing one's sword")
  * «Shurikenjutsu» (手裏剣術, lit. "The art of using a throwing star")
  * «Infinite Spear» (無限槍, Mugen Yari)

This means that there are still 4 unique skills that we don't know the
abilities for, of which one could explain Kirito's ability to briefly
withstand a killing blow.




## Asuna

### Theory 1: Kayaba kept his words to prevent Asuna from comitting suicide

Before the fight, Kirito had requested Kayaba to prevent from Asuna taking her
own life if he was to die, as Asuna threatened to commit suicide if that
happened. Quite possibly, Kayaba had set thing up to ensure that if Asuna went
to kill herself, she wouldn't actually die, confident that he would win (as he
was supposed to be the last boss on the 100th floor).

Otherwise, in [my answer](https://anime.stackexchange.com/questions/13007/how-
does-kirito-come-back-to-life-when-hes-fighting-heathcliff/13009#13009) to the
[question](https://anime.stackexchange.com/questions/14035/how-did-asuna-
survived#comment18023_14035) Mysticial linked to, I explain there is a time
delay before the NervGear kills Kirito in the real world. Seeing as Asuna had
in a way killed herself, Kayaba at that point might have prevented Asuna from
dying in the real world and put her in the holding area where she met with
Kirito later. After all, Kayaba was show to have a level of [honor and
fairness](http://swordartonline.wikia.com/wiki/Heathcliff#Personality) and
probably wanted to hold up his end of the deal. Remember that he paralyzed
everyone so no one would get in the duel between him and Kirito, yet he was
surprised to see that Asuna was still able to move.

### Theory 2: Sugou had been keeping Asuna alive

Another possibility is Sugou Nobuyuki. Asuna being in the holding area may
have been a stroke of luck, and Kayaba didn't notice that after SAO was
cleared, Sugou prevented 300 players from waking up for his experiments.
However, this runs off the theory that Asuna was not _just_ one of the 300,
and she was targeted to be isolated and trapped separately.

This is slightly backed up by 2 points:

  1. Sugou did say **he** was keeping Asuna alive, rather than her father who owned the company, and were more likely to use it to look after his daughter

  2. [The wiki](http://swordartonline.wikia.com/wiki/RECT_Inc.#Background) about RECT Progress's background says

> RECT Progress Inc. had set the 1st main goal of ALfheim Online to reach the
> top of the World Tree, but was later found to be impossible to complete. It
> was revealed that the World Tree's actual purpose was to hold the remaining
> 300 prisoners from SAO as test subjects in inhumane experiments.

This would indicate that since the release of ALO, Sugou was waiting for SAO
to be cleared.

## Kirito

As for how Kirito survived, please refer to my answer
[here](https://anime.stackexchange.com/questions/13007/how-does-kirito-come-
back-to-life-when-hes-fighting-heathcliff/13009#13009). (Originally, this
question only addressed Asuna, and I have only noticed that it's been edited
to address Kirito as well).

