The Sword Art Online anime series, based on the light novel series by Reki Kawahara, was first aired in Japan.
The original Sword Art Online light novel series by Reki Kawahara began publication.
Sword Art Online became available for streaming on international platforms, expanding its global audience.
A theatrical movie titled Sword Art Online: Ordinal Scale was released, continuing the story of the series.
Announcement was made for the anime adaptation of Sword Art Online Progressive series, a retelling and expansion of the Aincrad arc.
The full-dive virtual reality MMORPG Sword Art Online (SAO) is released with the Neuron Synchronization Display technology.
Players realize that they are trapped inside Sword Art Online; logging out is impossible and death in the game means death in the real world.
Players start the urgent goal to clear all 100 floors of Aincrad to escape the game and regain freedom.
Kirito and Asuna meet and start a strong partnership that develops into a romantic relationship while progressing through Aincrad.
Significant progress is made as the players clear the 75th floor of Aincrad, showing the progressing difficulty.
Kirito defeats the final boss on the 100th floor, clearing Aincrad and allowing all survivors to be freed from Sword Art Online.
Kirito uses his VR device to enter Alfheim Online, a new virtual game world, to rescue Asuna who is trapped there.
Kirito defeats Oberon to free Asuna and other players held captive in Alfheim Online.
Kirito confronts and defeats Death Gun, stopping the killings occurring in and out of the game.
Kirito, alongside Eugeo, explores the Underworld virtual world, revealing new mysteries with deep artificial intelligence.
Kirito and Eugeo confront and defeat the Administrator in the Underworld, seeking to save Alice and reveal AI truths.
Kirito awakens from his coma, recovering from aftereffects of the Underworld experience and reconnecting with friends.
