The Halloween Gambit (also known as the Müller–Schulze Gambit or Leipzig Gambit) is an aggressive chess opening gambit in which White sacrifices a knight early on for a single pawn. The opening is an offshoot of the normally staid Four Knights Game and is defined by the moves:
1. e4 e5
2. Nf3 Nc6
3. Nc3 Nf6
4. Nxe5
The theoretician Oskar Cordel reported in 1888 that Leipzig club players used the opening to dangerous effect, but he did not believe it was sound. Their name for it, Gambit Müller und Schulze, was not after any players by those names, but rather a jocular German equivalent of “Smith and Jones”, or, “Tom, Dick, and Harry”. The modern name “Halloween Gambit” was given by the German player Steffen Jakob, who explained that “Many players are shocked, the way they would be frightened by a Halloween mask, when they are mentally prepared for a boring Four Knight’s, and then they are faced with Nxe5”.
White’s objective is to seize the center with pawns and drive back Black’s knights. After 4… Nxe5, White usually plays 5. d4 (5.f4 does nothing for his development), after which Black can retreat the attacked knight to either g6 or c6.
Halloween Gambit with colors reversed
A similar gambit can be tried by Black: after 4.g3, Black can play 4…Nxe4!? This line is arguably sounder than its White counterpart because White’s 4.g3 has weakened his f3-square. Moreover, White cannot play the line recommended by Kaufman with colors reversed, because 5.Nxe4 d5 6.Nc3 d4 7.Bb5? dxc3 8.Nxe5? Qd5 9.Qe2? loses to 9…Qxh1+. However, with the pawn on g3, Nh4 is possible and it should be easier to castle.
