Berlin Gambit

The Berlin Gambit arises after 1. e4 Nc6 2. d4 d5 3. Nc3 dxe4 4. d5, so it belongs to the Nimzowitsch Defense as much as to the Van Geet Opening, and it can also be reached from 1. Nc3 by transposition. Rather than spend a tempo regaining the pawn on e4, White advances the d-pawn to evict the knight from c6. Black keeps the extra pawn, though it is an isolated e-pawn that leaves Black with doubled e-pawns, while White gains central space and time. The d- and e-files are half-open.

The main decision is where the knight goes. 4...Ne5 is the most common choice and leads into lines catalogued under the Nimzowitsch Defense, including its Scandinavian and Bogoljubow Variations and the Nimzowitsch Gambit. 4...Nb4 is the second most frequent retreat, putting the knight where it eyes d5 and c2, while the modest 4...Nb8 is a less common but respectable alternative. The engine rates the position as roughly balanced, and in online games White scores somewhat better than Black.