1st Prize Die Schwalbe, 1980
8+16. On which squares did captures occur and in what order?
The 8 wh. Pawns are the only missing units. They did not capture and never went beyond the barrier of bl. Pawns.
White is retropat (retracting -1. Ke8-f8 would walk into an impossible check). Obviously Black played last and must retract now, but then White will have to retract something. White is threatened by a pending retropat and the only way to give him retro-tempi is to uncapture the wh. Pawns. These wh. Pawns can then go back to the 2nd rank but this will only last for a few moves. Eventually, the North cage will have to be opened.
The cage only opens by driving a bl. unit on d8 so that the bl. Rooks and Queen can be extracted, freeing Wh. But only the bl. King can reach d8 (via a7) and the whole unlocking maneuver needs many moves, so that we must uncapture many wh. Pawns, on highest possible squares.
-1. Kg4xPh3 (only way to give one wh. retro-tempo)
-1 ... h2-h3+ (Wh. is retropat again)
-2. Kf3xPg4 (again, a necessity)
-2 ... g3-g4
-3. Ke4xPf3 (again, there is no choice)
-3 ... f2-f3+ (Wh. is retropat again, but now there is a choice. We can uncapture a wPe4 or remove the Bg2. It turns out we will need the B move later.)
-4. Kd5xPe4 e3-e4+
-5. Kc4xPd5 d4-d5 (now Wh. has a few retro-tempi available. But this is not enough)
-6. Kc5-c4 d3-d4+
-7. Kb6xPc5 c4-c5+
-8. Ka5xPb6 (gives Wh. a few more tempi before entering the cage via a7)
-8 ... b5-b6
-9. Kb6xPa5 a4-a5+
-10. N..-e2 (or B..-g2) b4-b5 (clear the b5 square)
-11. Nb5-a7 e2-e3 (or g2-g3)
-12. Ka7-b6 d2-d3
-13. Kb8-a7 c3-c4
-14. Kc8-b8 c2-c3
-15. Kd8-c8 a3-a4
-16. Qc8-d7 a2-a3 (now Wh. is retropat again. No more Pawn moves are available because the wh. Bishops and Rooks need entry points to go back home)
-17. Rd7-e7 (just in time)
-17 ... Re7-f7 (Wh. has avoided retropat and the position unlocks easily).
All 8 captures and their relative order can be precisely determined !! A fantastic composition.