I am trying to remember a puzzle position, or maybe was it originated from a real game, i dont remember.
After Rook c8, we have a nice zugzwang, which forces black to have as only legal move Rook from a7 to a8, making it en prise for white's rook.
Something like (white to move):
7R/rp6/pk6/p7/P7/8/1K6/8 w - - 0 1
I would like to know where is this puzzle/game from. I'm not sure that this was the exact position, but it was quite similar.