Ambivalence is played on a 6x6 square board. On each turn, each player drops a friendly stone on an empty cell. In the following cases, stones are transformed into neutral stones: Custodian: An enemy stone becomes neutral when placed between two friendly stones. Intrusion: Two enemy stones becomes neutral when a friendly stone is dropped between them. When the board is full, the player with more friendly stones wins. Ambivalence is listed as Ambivalente in 100 Strategic Games for Pen and Paper by Walter Joris.