Chess Opening Theory/1. e4/1...c6/2. d4/2...d5/3. Nc3/3...dxe4/4. Nxe4/4...Bf5/5. Ng3/5...Bg6/6. h4/6...h6/7. Nf3/7...Nd7/8. h5/8...Bh7/9. Bd3/9...Bxd3/10. Qxd3/10...e6/11. Bf4/11...Qa5

11...Qa5+
This move asks White to play c3. This stops White's hopes of castling queenside, and thus ends his kingside attack.