After the group defeats the Skull Reaper, suffering 14 casualties in the battle, Kirito deduces that Heathcliff is, in fact, Akihiko Kayaba himself. Akihiko paralyses everyone except Kirito, and then offers Kirito the chance to face him in a one-on-one duel where, should Kirito win, Akihiko would log out all the remaining players. After giving his best wishes to the others, Kirito accepts the challenge but is unable to overcome Akihiko's absolute defense and intimate understanding of the game's mechanics. As Akihiko readies the finishing blow, Asuna overcomes her paralysis and takes the hit instead, losing all her HP and disappearing as a result. Distraught by Asuna's passing, Kirito loses the will to fight and receives a fatal stab from Akihiko. However, at the point of passing, Kirito remembers Asuna's belief in him and manages to regain enough substance to defeat Akihiko using Asuna's sword. They are bothhuged simultaneously and the game is declared cleared on November 7, 2024. Kirito then awakens high above the game world, where he finds both Asuna and Akihiko. Akihiko informs Kirito and Asuna that he has logged out all the other players as promised, and also explains his motives for creating Sword Art Online before disappearing. Kirito and Asuna then tell one another their true names, Kazuto Kirigaya and Asuna Y?ki, and embrace each other as the world falls apart. To his surprise, Kazuto awakens in a hospital in the real world and, despite being physically weak, sets off to search for the real Asuna.
In the near future, a Virtual Reality Massive Multiplayer Online Role-Playing Game (VRMMORPG) called Sword Art Online has been released where players control their avatars with their bodies using a piece of technology called Nerve Gear. One day, players discover they cannot log out, as the game creator is holding them captive unless they reach the 100th floor of the game's tower and defeat the final boss. However, if they die in the game, they die in real life. Their struggle for survival starts now...