29... gxf1=Q+30. Rxf1Bxf131. Nxd6Qd332. Qg4
There are 37,816 more.
Every one is the critical moment from a real grandmaster game, and no position is ever shown twice.
Keep playingFound by reading 318,096 games from 1,761 grandmasters, and checked by the engine before it reached you.