12+14. Weiß und Schwarz nehmen insgesamt 80 von Weiß gewünschte Einzelzüge zurück; dann Matt in einem Zug!
White captures are c6xd7 (the c-pawn must have promoted to a rook,
since Rh1 was captured on h1 or g1) and bxa. Black captures are Rh1,
axb, and h7xg6xf5.
During the first phase, white makes waiting moves with his king between
b8 and a8, while black retracts:
-1. Kd8-c8 -2. Ke8-d8 -3. Kf8-e8 -4. Bh7-g8 -5. Kg8-f8 -6. Bg8-h7
-7. Kh8-g8 -8. Kh7-h8 -8. Kh6-h7 -9. Kg5-h6 -10. Kf4-g5 -11. Ke4-f4
-12. Kd4-e4 -13. Kc4-d4 -14. Kb3-c4 -15. Kc2-b3 -16. Kd1-c2 -17. Ke1-d1
-18. Kf2-e1 -19. Kg1-f2 -20. Kf2xRg1
During the next phase, white makes waiting moves with his rook between
g1 and h1, while black retracts:
-21. Ke1-f2 -22. Kd1-e1 -23. Kc2-d1 -24. Kb3-c2 -25. Kc4-b3 -26. Kd4-c4
-27. Ke4-d4 -28. Kf4-e4 -29. Kg5-f4 -30. Kh6-g5 -31. Kh7-h6 -32. Kh8-h7
-33. Bh7-g8 -34. Kg8-h8 -35. Kf8-g8 -36. Ke8-f8 -37. Kd8-e8 -38. Kc8-d8
-39. Rd8-d7
and now white plays forward 1. Rc7#.
Solution by Philippe Schnoebelen
