Poka Yoke

Poka Yoke is a combinatorial game for two players. It's the follow-up to Tixel and Regatta.

The rules of Poka Yoke are exactly like the Tixel rules (see below) with the addition of the following 'piece promotion' rule:

If in a single turn a player picks up 1 of her own pieces (during a bonus move) to end the turn, then the picked up piece is promoted to a Regatta piece. In any single game at most 2 pieces per player can be promoted in this fashion.

Brief description of the Tixel rules: On a turn, a player can either place a new Tixel piece or move one of her own Tixel pieces already on the board. A Tixel piece can be "active" or "inactive"; only active pieces, which are at a 45º angle, may be moved. Making pieces inactive is done by moving next to or passing an active piece. Chaining moves is important as this temporarily unlocks three additional move types (aside from placing or moving a piece). If a piece 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 piece, she can now remove a piece from the board, activate an inactive piece, or pivot an active piece to reorient its hollow side.