Click on the third or sixth rank to set the en passant target square.

Book: ∞ / 0

# move proof disproof
1 Rd8 0
2 Ra7 0
3 e4 0
4 h5 0
5 d5 0
6 Rf8 0
7 Rg8 0
8 d6 0
9 Re8 0
10 Rb8 0
11 Bb7 0