One more game. I played it against myself, trying to find a forced win for
black. As surprise, white won!
1. kg7 (*Bh8) Ph7 // white unpromotes bishop, there were no uncaptures
possible, so a regular unmove is allowed
2. kh8 (*Pg7)?? Pf6 (*pg7)!
White wins as black doesn't have any legal unmove now.