Hidden Move Go
Before the game, both players secretly pick 3 points on the board for their hidden moves. A simple way to record the hidden moves is to draw a square and write for example "3-4" or "10-10" in the general area of the moves. During the game, when a hidden move would affect play, the player reveals the hidden move and places it on the board. If the hidden move makes the opponent's move illegal, he can then choose a different move.
- White tries to play on top of a hidden move. Black reveals the hidden move and places it on the board. White gets to pick a new move.
- White uses his own hidden stone to capture enemy stones. He reveals his hidden move, and makes his own move to complete the capture.
Collisions: If both players make hidden moves on the same point, whoever reveals he has a hidden move there first gets to claim it. Alternatively a neutral judge can check the hidden moves before the game starts for collisions.