The free lines of this chapter, each one trainable move by move.
Main Line
… 4... d6 5. f4 Ng4 6. f5 h5 7. Nh3
3...c6
… 3. Bc4 c6 4. d4 d5 5. exd5 cxd5 6. dxe5 dxc4 7. Qxd8+ Kxd8 8. exf6 gxf6 9. Bf4 Nc6 10. O-O-O+ Ke8 11. Nd5 Rb8 12. Nf3 Be6 13. Bxb8 Nxb8 14. Nxf6+
3...c6
… 3. Bc4 c6 4. d4 d5 5. exd5 cxd5 6. dxe5 dxc4 7. Qxd8+ Kxd8 8. exf6 gxf6 9. Bf4 Nc6 10. O-O-O+ Bd7 11. Nge2
3...c6
… 3. Bc4 c6 4. d4 exd4 5. Qxd4 Be7 6. Nf3
3...c6
… 3. Bc4 c6 4. d4 exd4 5. Qxd4 c5 6. Qe5+ Be7 7. Qg3 d5 8. Bxd5 O-O 9. Be3 Nc6 10. O-O-O Qb6 11. e5
3...c6
… 3. Bc4 c6 4. d4 exd4 5. Qxd4 d6 6. Bf4
4...O-O
… 4. d3 O-O 5. f4 exf4 6. Bxf4 c6 7. d4 Bb6 8. Bd6 Ba5 9. Bxf8 d5 10. b4 Bc7 11. Bxg7
4...O-O
… 4. d3 O-O 5. f4 exf4 6. Bxf4 c6 7. d4 Bb4 8. Ne2 Nxe4 9. O-O d5 10. Nxe4 dxc4 11. N2g3
4...O-O
… 4. d3 O-O 5. f4 d6 6. f5 Nc6 7. Bg5 h6 8. h4
4...h6
… 4. d3 h6 5. f4 exf4 6. Bxf4 Nc6 7. Nf3
4...h6
… 4. d3 h6 5. f4 d6 6. Nf3 Bg4 7. fxe5 dxe5 8. Bxf7+ Ke7 9. Bb3 Qe8 10. h3 Qh5 11. Rf1
4...h6
… 4. d3 h6 5. f4 d6 6. Nf3 Nc6 7. Na4
4...c6
… 4. d3 c6 5. Nf3 d6 6. O-O O-O 7. a3
4...c6
… 4. d3 c6 5. Nf3 d5 6. Bb3 dxe4 7. Ng5 O-O 8. Ngxe4 Nbd7 9. O-O
5...exf4
… 5. f4 exf4 6. Nf3 Ng4 7. d4 Bb6 8. Bxf4 Nc6 9. Bg5 f6 10. Bf4
5...Bg4
… 5. f4 Bg4 6. Nf3 Nc6