Ruy Lopez:Noah's Ark Trap

A trap that catches White’s light-squared bishop: Black’s pawns advance with ...c5 and ...c4, and the bishop on b3 has nowhere to go. The name says it is as old as the ark.

It is reached after 16 moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 b5 5. Bb3 d6 6. d4 Nxd4 7. Nxd4 exd4 8. Qxd4 c5. It is a line of the Ruy Lopez.

White is to move and has 45 legal moves. Over the next four moves — two for each side — the game can branch into 1,839,479 different games. Those games reach 573,454 different positions: most positions can be reached in more than one way, 3.2 on average.

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