It's revealed that following the battle with Administrator, and following his failed connection back to the real world, Kirito has been left without emotions and his ability to speak. ... Although this seems like a coma, Kirito has maintained his motor functions and is responsive to things.

Does Kirito ever get out of his coma?

Sword Art Online: Alicization began the War of Underworld arc with a comatose Kirito, but after teasing his return to action for the last few episodes Kirito has finally woken up and made his big return to the series in the newest episode.

Why is Kirito unconscious?

Sword Art Online: Alicization has been a much different season from the first two because it started off with Kirito taking a nearly fatal blow and going unconscious when injected with poison. ... After he was injected with poison by Johnny Black in the real world, Kirito had been knocked unconscious.