Despite the minus pawn Black enjoys a clear initiative and went on to win.

Initiating a majority attack to soften up the enemy kingside.

2...Bxh4? 3.Qg4+-

Black can only keep the material balance by surrendering the b1-h7 diagonal.

Fixing a weakness on h7.

9...dxc4 10.Bxc4 Nd5 11.Bxd5 exd5 12.e6! +-

followed by Rc3 with a decisive attack.

Preparing ...h5-h4 in order to fix the g3-square and indirectly weaken the f4-pawn. It is important to realize this idea before White manages to play 2 Bf3 followed by g2-g3, after which he could meet ...h5-h4 by g3-g4.

The most powerful way of doubling the rooks.