King's Indian Defense: Bayonet Attack
1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 O-O 6.Be2 e5 7.O-O Nc6 8.d5 Ne7 9.b4
The Bayonet Attack is a sub-variation of the Classical Variation against the King's Indian. After the creation of mutual pawn chains, White's 9.b4 prepares to attack the base of Black' chain by c4-c5, while also leaving the knight on f3 so that it might go to g5 and e6 if Black plays ...f5.
Pros:
- White's play is more central than after other ninth moves (9.Ne1, 9.Nd2)
- White runs less risk of getting checkmated than after other ninth moves
Cons:
- Very theoretical
- Unlike 9.Ne1 or 9.Nd2, the Bayonet allows 9...Nh5
- Black can exploit the advance of the b-pawn with 9...a5.