Mate in three vs Black to move

Start Analysis Engine to see Solution #4156 Chess: 5334 Problems, Combination | Cleanchess.com | 1 Jul 2017

1014135

[Event "Start Analysis Engine to see Solution #4156 Chess: 5334 Problems, Combination"] [Site "Cleanchess.com"] [Date "2017.07.01"] [Round "0"] [White "Mate in three"] [Black "Black to move"] [FEN "7k/pp2Q1pp/5r2/P2P4/3Pb1P1/4Ppq1/1P1R3N/2r2R1K b - - 0 1"] 1... f2+ 2. Qxe4 Qg1+ 3. Rxg1 fxg1=Q# *

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