Puyo Puyo 20th Anniversary is an installment in the Puyo Puyo series. Gameplay-wise, the basic elements of Puyo Puyo are still there - eliminate Puyos and bury your opponents in a landslide of Nuisance Puyos. But in addition to the standard "Puyo Puyo", "TSU" and "Fever" rules, there are also new gimmick modes and modes returning from past Puyo Puyo games. The most noticeable rule change in the game, however, may be the "Pair Puyo" mode, a co-op mode where two teams of two players battle it out to end all their opponents' lives.
In the standard Story Mode, players take one of 24 characters through their own 8-stage course, which all fit into the big picture as Ekoro (Ringo Andou's antagonist from Puyo Puyo 7) rises again to cause chaos to the world. In addition, several of the characters can have alternate voices, and still others can have alternate costumes. The battle mode is still intact, with up to 4 (8 in the DS and 3DS versions) players fighting it out across the various gameplay modes.