Breyer Variation, Stein Attack

The Stein Attack is the Breyer Variation line in which Black answers White's King's Indian Attack arrangement by fianchettoing the king's bishop as well: 3. Nd2 g6 4. Ngf3 Bg7 5. g3 e5 6. Bg2 Ne7 7. O-O O-O 8. b4. With both kings castled short and the e4–d3 and d5–e5 pawns facing each other in tension, 8. b4 moves White's play to the queenside, gaining space and preparing b5 to undermine the c6-pawn that supports Black's center.