1. Main line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 Choose a line 1. Main line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 2. Blockade Line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 8. d5 Na5 9. Nd2 c5 10. Qc2 e5 3. Donner Line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 8. d5 Na5 9. Nd2 c5 10. Qc2 Rb8 11. b3 b5 12. Bb2 bxc4 13. bxc4 Bh6 4. Korchnoi Line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 8. h3 Rb8 9. Be3 b5 10. Nd2 Close 1. Main line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 2. Blockade Line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 8. d5 Na5 9. Nd2 c5 10. Qc2 e5 3. Donner Line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 8. d5 Na5 9. Nd2 c5 10. Qc2 Rb8 11. b3 b5 12. Bb2 bxc4 13. bxc4 Bh6 4. Korchnoi Line 1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O Nc6 7. Nc3 a6 8. h3 Rb8 9. Be3 b5 10. Nd2 Next