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

EGTB: win in 4 half-moves

# move score
1 Kb4 win in 3 half-moves
2 Kb5 win in 3 half-moves
3 Ka7 win in 7 half-moves
4 Kb7 win in 7 half-moves
5 Kc7 win in 7 half-moves
6 Ra7 win in 7 half-moves
7 Ra5 win in 9 half-moves
8 Ka5 win in 29 half-moves
9 Ka3 draw
10 Kb3 draw
11 Kc8 draw
12 Ra6 draw