What is just a zugzwang is clear. This is when, in a normal good position, a side is forced to make a move, and any move made leads to a loss. Accordingly, in Retro moves are made not forward, but backward. That is, the same thing, but now with the return of the move. Of course, a situation where black does not have the last code that preserves castling can be called a zugzwang. They return the move - lose the right to castling - lose. But it's too easy. And no one, of course, will call this retro zugzwang.
Therefore, let's complicate the conditions of the task:
- The initial position should not be lost for black.
- But the return of any move makes it lost.
- At the same time, the return of the move by black does not lead to any direct consequences. Black does not lose the right to castling, for example.
Is it possible to create such a position?