Final position — Black is winning
King's Gambit: Wins the Exchange (Unknown–Olson)
Black wins in 9 moves with a decisive material gain. (Unknown - Olson, Boston 1979)
The moves
| 1. | e4 | e5 |
| 2. | f4 | d5 |
| 3. | exd5 | e4 |
| 4. | d3 | Nf6 |
| 5. | dxe4 | Nxe4 |
| 6. | Nc3 | Qh4+ |
| 7. | g3 | Nxg3 |
| 8. | Nf3 | Qe7+ |
| 9. | Kf2 | Nxh1+ |
How the King's Gambit: Wins the Exchange (Unknown–Olson) works
The King's Gambit: Wins the Exchange (Unknown–Olson) is a classic chess opening trap arising from the King's gambit. In this line Black wins decisive material by move 9, punishing a natural-looking but losing idea from White.
The full sequence runs 1.e4 e5 2.f4 d5 3.exd5 e4 4.d3 Nf6 5.dxe4 Nxe4 6.Nc3 Qh4+ 7.g3 Nxg3 8.Nf3 Qe7+ 9.Kf2 Nxh1+. 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 (Unknown - Olson, Boston 1979). Recognising it early lets you either spring it as Black or sidestep it as White.
Practice this trap move-by-move
Open the King's Gambit: Wins the Exchange (Unknown–Olson) 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.