1.Nh3 h6 2.e3

The main line is 2...e6, which can be reached via 1.e3 e6 2.Nh3 h6.

Black can try 2...f5, but after 3.Qh5 g6 4.Qh4 Nf6 5.Nc3 c6 6.Nf4 white will play Nxe6 or Nxg6 and is a pawn up without compensation. White can also play 3.Nc3 or 3.Nf4.