Mate in three vs Black to move

Start Analysis Engine to see Solution #4158 Chess: 5334 Problems, Combination | Cleanchess.com | 1 Jul 2017

1014137

[Event "Start Analysis Engine to see Solution #4158 Chess: 5334 Problems, Combination"] [Site "Cleanchess.com"] [Date "2017.07.01"] [Round "0"] [White "Mate in three"] [Black "Black to move"] [FEN "5QN1/1p5p/1p1P2p1/2P1pp2/1P2NkP1/1P3n2/r2q2P1/6RK b - - 0 1"] 1... Qxg2+ 2. Rxg2 Ra1+ 3. Rg1 Rxg1# *

http://chessmicrobase.com/microbases/11081/games/1014137?token=atuh4dr6