Haunted Chess

In a capture, a ghost of the captured piece stays on the capture square; the piece reappears once the capturing piece moves again; in case of several ghosts on the same square (i.e. consecutive captures), the older ones definitely disappear; only the more recent is subject to ''reappearance''; in the special case of en passant, the ghost square can be passed through but not occupied until the ''reappearance'' (when the capturing pawn moves again).