In the Tetrissa game, players must complete lines by moving differently shaped pieces, which descend onto the playing field. The completed lines disappear and grant the player points, and the player can proceed to fill the vacated spaces.
The game ends when the playing field is filled. The longer the player can delay this inevitable outcome, the higher their score will be. In multiplayer games, the players must last longer than their opponents, and in certain versions, players can inflict penalties on opponents by completing a significant number of lines. Some adaptations have provided variations to the game’s theme, such as three-dimensional displays or a system for reserving pieces.