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

EGTB: win in 4 half-moves

# move score
1 Rd7 win in 3 half-moves
2 Rc7 draw
3 Kb6 loss in 2 half-moves
4 Kb7 loss in 2 half-moves
5 Kd6 loss in 2 half-moves
6 Kd7 loss in 2 half-moves
7 Kd8 loss in 2 half-moves
8 Ke6 loss in 2 half-moves
9 Ke8 loss in 2 half-moves
10 Kf6 loss in 2 half-moves
11 Kf7 loss in 2 half-moves
12 Kf8 loss in 2 half-moves
13 Ra8 loss in 2 half-moves
14 Rb7 loss in 2 half-moves
15 Ka5 loss in 1 half-moves
16 Kb5 loss in 1 half-moves