Mirror

In a mirror chess problem, your task is to achieve a certian goal, often checkmating, based on your opponent being committed to mirroring your every move. You can't make moves that are impossible to mirror, unless the move is a checkmate. For example, after 1. e4 e5 2. Qh5 Qh4, you can't play 3. Qxh4, since that would be impossible to mirror.