Ditto chess

In Ditto Chess, whenever the player to move can legally copy the opponent's previous move, they must do so. If they can't legally copy the move, they may play any legal move. A move is considered a copy if it meets the following conditions:

1) the type of piece that's used is the same

2) the copying move starts and ends on the horizontally mirrored squares of the original move (e.g. Qa1-b2 is a copy of Qa8-b7)

3) the moves both capture the same type of piece (or both capture no piece at all)