Bongcloud Attack

A joke opening that became an internet meme: the king steps forward on move two and blocks its own bishop. Even Magnus Carlsen and Hikaru Nakamura have played it in online games.

It is reached after 3 moves: 1. e4 e5 2. Ke2.

Black is to move and has 29 legal moves. Over the next four moves — two for each side — the game can branch into 484,431 different games. Those games reach 166,045 different positions: most positions can be reached in more than one way, 2.9 on average.

No later position on this line has a name of its own in the Lichess opening list: the names end here.

No other order of these moves reaches this position: each move depends on the one before.