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

Book: ∞ / 0

# move proof disproof
1 a6 0
2 Kd6 0
3 Kc6 0
4 Ke7 0
5 Bb7 0
6 Kd8 0
7 Ke6 0
8 Ke8 0
9 Nc6 0
10 a5 0
11 Na6 0
12 Ba6 0
13 c6 0
14 c5 0