Richter-Veresov Attack

Named after Kurt Richter and Gavriil Veresov: White develops the queen’s knight to c3 and pins with Bg5.

It is reached after 5 moves: 1. d4 Nf6 2. Nc3 d5 3. Bg5.

Black is to move and has 28 legal moves. Over the next four moves — two for each side — the game can branch into 886,576 different games. Those games reach 296,574 different positions: most positions can be reached in more than one way, 3 on average.

The Lichess opening list names 7 further lines after this position, such as Two Knights System (3... Nbd7 4. Nf3) and Boyce Defense (3... Ne4).

The same moves can be played in 6 different legal orders that all reach this position. For example 1. Nc3 Nf6 2. d4 d5 3. Bg5, which starts as the Van Geet Opening.