The anime centers around a boy named Kouta Kouka (Kouka Kouta in Japanese name order, an apparent wordplay on Coca-Cola). Kouta strives to be the world's best Bottle King at the Bottle Battles in the virtual Drink World. He comes across his Bottleman partner Colamaru and then wages battles with various rivals. (Source: ANN)

When the popular online game Yggdrasil is shut down, a lonely player named Momonga decides to stay logged in and take over this digital frontier.

When the popular online game Yggdrasil is shut down, a lonely player named Momonga decides to stay logged in and take over this digital frontier.

Episode 0 of that aired as an April Fool's joke. Shigeru Akagi, a teenage mahjong genius, repeatedly defeats seasoned Jyanshis thanks to his bravery and drive. However, Shigeru’s fiercest nemesis, Iwao Washizu, enters the Mahjong Soul with enormous wealth and good fortune to resume his battle with Shigeru.