Pnickies is a puzzle game similar to Puyo Puyo, where you stack differently coloured jelly blocks and ideally form chain reactions. The difference to Puyo Puyo is that the blocks do not disappear once a certain number of same coloured ones are connected, but instead there are star blocks which also come in the same colours as the normal blocks. To make blocks disappear the player has to form a connected group of same coloured blocks that contain two star blocks. As soon as the 2nd star block is added the affected group goes away and any blocks that were on top of parts of this group will fall down.
The game is quite basic and only has single player, two player versus, and two player simultaneous modes, but no way to play against a CPU opponent.
In versus mode the players can send black blocks to their opponent, where the number of blocks sent is influenced by how many blocks were made to disappear. Big chain reactions with result in a huge amount of black blocks being sent to the other player. These black blocks can only be destroyed by destroying normal blocks adjacent to them.