Chess Opening Theory/1. e4/1...e5/2. Nf3/2...f5/3. Bc4/3...fxe4/4. Nxe5

Mayet attack C40 Latvian gambit → Mayet attack → 3...fxe4 4. Nxe5 Now White takes Black's pawn and threatens Nf7, which would fork Black's queen on d8 and rook on h8. Black can choose to defend this threat, ignore the threat or set a trap. 4...d5, the Polerio-Svedenborg variation, directly defends against the Nf7 threat by blocking the bishop on c4's vision of f7 and attacking it. This is the most common move by far. 4...Qg5!? sets a trap. It seems to blunder the fork 5. Nf7?!, but after 5...Qxg2! 6. Rf1 Bg4! Black has an attack where White has to be precise. 4...Nf6?, the Corkscrew countergambit, is just too much. After 5. Nf7 Qe7 6. Nxh8, Black plays the Corkscrew Gambit with 6...d5 and hopes for 7. Bb3?? Bg4!, but if 7. Be2! is played the gambit is proven unsound and Black is down a rook.