Benko Gambit

Named after Pal Benko; also called the Volga Gambit. Black gives a pawn for long-lasting pressure along the a- and b-files.

It is reached after 6 moves: 1. d4 Nf6 2. c4 c5 3. d5 b5.

White is to move and has 31 legal moves. Over the next four moves — two for each side — the game can branch into 594,976 different games. Those games reach 206,209 different positions: most positions can be reached in more than one way, 2.9 on average.

The Lichess opening list names 23 further lines after this position, such as Benko Gambit Accepted (4. cxb5 a6) and Benko Gambit Declined, Bishop Attack (4. Bg5).

The same moves can be played in 12 different legal orders that all reach this position. For example 1. c4 Nf6 2. d4 c5 3. d5 b5, which starts as the English Opening.