Well, 1.Ng6 jumps out immediately- black has to capture the knight to save the queen since the queen has no retreat square, but this opens a pin on the rook at e6 to the king, and white can capture the rook with 2.Rxe6 winning an exchange:
1.Ng6 fg6 2.Re6 Re6 3.Qe6+.
Black has some options at his first move- he can play 1....Re1, but now the f-pawn is pinned to the queen, so white will just can just retake at e1 first. Black can try to muddle things with 2.....b5, but white will just take at f8 and d7 giving black a choice of taking at e1 again but will lose the knight at f6 with check before white retakes at e1 with the f3 knight, or take d7 but lose the rook at e8:
1.Ng6 Re1 2.b5 Nf8 3.bc4 Nd7 4.Re1 Nf6+ 5.gf6 Ne1 winning.
Finally, black can try 1....b5 first, but this still loses the exchange and a pawn:
1.Ng6 b5 2.Nf8! bc4 3.Ne6 fe6 4.Rc4 winning.