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

EGTB: win in 4 half-moves

# move score
1 Ka5 win in 3 half-moves
2 Kb6 loss in 44 half-moves
3 Ka7 loss in 36 half-moves
4 Kb7 loss in 36 half-moves
5 Kb5 loss in 2 half-moves