Tixel is a combinatorial game for two players. The name comes from the playing pieces, which are basically pixels (squares) with a curved indentation on one of their edges. Tixels are "directional", meaning that their orientation is relevant. On a turn, a player can either place a new tixel or move one of her own tixels already on the board. A tixel can be "active" or "inactive"; only active tixels, which are at a 45º angle, may be moved. Making tixels inactive is done by moving next to or passing an active tixel. Chaining moves is important as this temporarily unlocks three additional move types (aside from placing or moving a piece). If a tixel that is moved is made inactive at its end position — i.e., it's sacrificed — a player can take an extra move if she so chooses; aside from placing or moving a tixel, she can now remove a tixel from the board, activate an inactive tixel, or pivot an active tixel to reorient its hollow side. Tixel: Tix Expansion Pieces consists of four extra pieces for each player. These expansion pieces are different from regular pieces in that they are completely square instead of being hollow on one side. For each expansion piece used, remove one tixel from the game. The expansion pieces can be used to add variety to games, but they can also be used to handicap a stronger player. Simply give the stronger player more expansion pieces compared to the weaker player. With two expansion sets, the original Tix game can also be played on the Tixel board.