Uncommon Notation: O-O-O#

@parker-laneem, please stay on topic

I can't find it right now and I'm not sure if it really qualifies, but in one game I used my bishop to prevent my opponent from castling for nearly 20 moves, then finally blocked the bishop and allowed them to castle because they would be walking into an M2 if they did.

My opponent then proceeded to castle without any hesitation. What followed was a checkmate not unlike the one Kramnik faced after his "blunder of the century" against Deep Fritz. The checkmating move was a common one (Qxh7#) but I still look upon it fondly for the fact that I completely bamboozled my opponent by denying them something they really wanted to do — until I finally allowed them to do it at the worst possible time. The first move before the mate was also a double check, which I think makes it unique enough to include here.