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

Book: ∞ / 0

# move proof disproof
1 f6 0
2 Ke6 0
3 Na6 0
4 Ra6 0
5 Ra7 0
6 Nf6 0
7 a4 0
8 Nc6 0
9 Kc7 0
10 h5 0
11 Kd6 0
12 Bb7 0
13 e5 0
14 Bg7 0
15 e6 0
16 f5 0
17 Ba6 0
18 Kc6 0
19 Kd8 0
20 Ke8 0