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

EGTB: win in 4 half-moves

# move score
1 Kb6 win in 3 half-moves
2 Rb2 draw
3 Kb8 loss in 2 half-moves
4 Kc3 loss in 2 half-moves
5 Kc4 loss in 2 half-moves
6 Kc5 loss in 2 half-moves
7 Kc6 loss in 2 half-moves
8 Kc8 loss in 2 half-moves
9 Kd3 loss in 2 half-moves
10 Kd5 loss in 2 half-moves
11 Kd6 loss in 2 half-moves
12 Kd7 loss in 2 half-moves
13 Kd8 loss in 2 half-moves
14 Ke3 loss in 2 half-moves
15 Ke4 loss in 2 half-moves
16 Ke5 loss in 2 half-moves
17 Ra7 loss in 2 half-moves
18 Rb1 loss in 2 half-moves
19 Rb3 loss in 2 half-moves
20 Rb4 loss in 2 half-moves
21 Rb5 loss in 2 half-moves
22 Rb6 loss in 2 half-moves
23 Rb8 loss in 2 half-moves