Twixt is a cooperative sculpture making game in which two players work together to create a twisting, two-color sculpture. There are a few variants of the game but they all share a set of universal rules. The object of the game is to create emergent forms while collectively placing as many pieces as possible.
To begin play, each player chooses a color. Players take turns making moves. Each move consists of the placement of a single piece within the bounds of the 4x4x4 grid. Each piece must align to the grid and fit entirely within the bounds of the board. Each piece must balance and is invalid if it topples or is adjusted after placement. The game is over when neither player can make a move.