.hack//Roots

In 2015, CC Corporation's datacenter caught on fire destroying "The World". By splicing in data from what would have been another project, CC Corp. was able to rebuild the game. In 2016, "The World R:2" was released. .hack//Roots covers the time Haseo spent with Shino and Ovan in the guild known as the Twilight Brigade, before the .hack//G.U. PS2 games.

Synopsis from Anime News Network