Final position — Black is winning
Queen's Gambit Declined, 4.Bg5: Opening Trap #2
Black wins in 18 moves with a decisive material gain. (50 Opening Traps,Part 1 - A mousetrap for rooks - D57 - https://lichess.org/@/CHESSLUCAFD)
The moves
| 1. | d4 | d5 |
| 2. | c4 | e6 |
| 3. | Nc3 | Nf6 |
| 4. | Bg5 | Be7 |
| 5. | Nf3 | O-O |
| 6. | e3 | h6 |
| 7. | Bh4 | Ne4 |
| 8. | Bxe7 | Qxe7 |
| 9. | cxd5 | Nxc3 |
| 10. | bxc3 | exd5 |
| 11. | Bd3 | Bg4 |
| 12. | Rb1 | Nd7 |
| 13. | Rxb7 | Nb6 |
| 14. | Qb3 | Bc8 |
| 15. | Rxb6 | axb6 |
| 16. | Qxd5 | Be6 |
| 17. | Qe4 | f5 |
| 18. | Qe5 | Ra5 |
How the Queen's Gambit Declined, 4.Bg5: Opening Trap #2 works
The Queen's Gambit Declined, 4.Bg5: Opening Trap #2 is a classic chess opening trap arising from the Queen's Gambit Declined, 4.Bg5. In this line Black wins decisive material by move 18, punishing a natural-looking but losing idea from White.
The full sequence runs 1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Bg5 Be7 5.Nf3 O-O 6.e3 h6 7.Bh4 Ne4 8.Bxe7 Qxe7 9.cxd5 Nxc3 10.bxc3 exd5 11.Bd3 Bg4 12.Rb1 Nd7 13.Rxb7 Nb6 14.Qb3 Bc8 15.Rxb6 axb6 16.Qxd5 Be6 17.Qe4 f5 18.Qe5 Ra5. Each move looks reasonable, which is exactly why the trap is so effective over the board — White walks into it while trying to play "normal" developing moves.
This pattern is well known from master and correspondence play (50 Opening Traps,Part 1 - A mousetrap for rooks - D57 - https://lichess.org/@/CHESSLUCAFD). Recognising it early lets you either spring it as Black or sidestep it as White.
Practice this trap move-by-move
Open the Queen's Gambit Declined, 4.Bg5: Opening Trap #2 in the Trapsterapp to play it out on a live board, drill it in practice mode, and learn how to avoid it when it's set for you — along with the full library of chess traps and gambits, fully offline.