Scandinavian Defense:Portuguese Gambit

It is reached after 6 moves: 1. e4 d5 2. exd5 Nf6 3. d4 Bg4. It is a line of the Scandinavian Defense.

White is to move and has 34 legal moves. Over the next four moves — two for each side — the game can branch into 1,344,329 different games. Those games reach 482,745 different positions: most positions can be reached in more than one way, 2.8 on average.

The Lichess opening list names 8 further lines after this position, such as Classical Variation (4. Nf3) and Wuss Variation (4. Be2).

The same moves can be played in 8 different legal orders that all reach this position. For example 1. d4 d5 2. e4 Nf6 3. exd5 Bg4, which starts as the Queen's Pawn Game.