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

EGTB: win in 4 half-moves

# move score
1 Na6 win in 3 half-moves
2 Kb7 loss in 2 half-moves
3 Kc7 loss in 2 half-moves
4 Kd8 loss in 2 half-moves
5 Nc6 loss in 2 half-moves
6 Kd7 loss in 1 half-moves
7 Nd7 loss in 1 half-moves