Scotch Game:Scotch Gambit

It is reached after 7 moves: 1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Bc4. It is a line of the Scotch Game.

Black is to move and has 32 legal moves. Over the next four moves — two for each side — the game can branch into 1,723,205 different games. Those games reach 566,011 different positions: most positions can be reached in more than one way, 3 on average.

The Lichess opening list names 8 further lines after this position, such as Haxo Gambit (4... Bc5) and London Defense (4... Bb4+).

The same moves can be played in 24 different legal orders that all reach this position. For example 1. Nf3 e5 2. e4 Nc6 3. d4 exd4 4. Bc4, which starts as the Zukertort Opening.