1.Nf3 f6 2.e4 d5 3.Nc3 b5 4.d4 Nh6

White can play:

5.Ne5 Ng4 6.f4 (or 6.Nxg4 c6 7.e5) 6...Ne3 (or 6...fxe5 7.f5 Ne3; 7...e6) 7.Bxe3 Bg4 8.Nxg4 e6 (or 8...e5),

5.Bxh6 Bg4 6.e5 (6.exd5 g6) 6...e6,

5.g4 Bxg4 (or 5...e5).