Puyo Puyo Fever

The basic game mechanics are mainly similar to those of Puyo Puyo : the player has a 6x12 board, and must decide where to place incoming groups of variously colored blobs, or puyo . After placing each set of puyo, any groups of four or more of the same colored adjacent puyo will pop. Any above will fall down and can form more groups for a chain reaction. Each time groups of puyo pop, the player will score points and send "trash" (aka "garbage" and "nuisance") to their opponent.

Garbage temporarily gets stored in a bar above the playfield, represented by symbols and warning the player of an incoming amount of garbage. These trash puyo are colorless and will only pop when puyo next to them do so, rather than in groups as normal. These will only fall if the player fails to make a chain, and trash falls in groups of 30 (one rock) at a time. When a player's board fills up, either if they cannot make groups or if they are sent a large amount of trash (usually the latter), they lose and the other player will win.

A new addition to the game mechanics is Fever mode, which occurs when a bar in the middle of the screen is filled up. To fill the bar, one must offset (or counterattack) the trash being sent to the field by the opponent. Every chain, which is a single popping of puyo, will fill one space in the fever meter until it is full, which is when fever activates. In Fever mode, a pre-designed chain will fall onto an empty field.

In a limited amount of time, one must find a trigger point in the puzzle, which will cause a large chain to go off and attack the opponent. Once a chain is made, another puzzle falls, bigger and more complicated than the previous one. This keeps occurring until time runs out, then it returns the player to their original field. The Nintendo DS version supports 2 to 8 players, as opposed to the others, which only support 2 or 4.

In this mode, one can play as any available character. The GameCube, Xbox, and PS2 versions used 3D models for the Puyos instead of the sprites used in all other versions. There is also an Endless mode, where one can practice fever mode, complete small tasks as they are given, or play the original game, but the grid and all clear rules remain the same as they do in Fever, so it is not exactly classic.