13 Oct 20
@greenpawn34 saidThis is basically the solution idea right here.
[pgn]
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
1. b4 c5 2. b5 Nc6 3. bxc6 d6 4. c7 Bd7 5. c8=N e6 6. Ne7 b6 7. Ng6 hxg6 8. c3 Rh4 9. Qc2 Ra4 10. e4 b5 11. Bc4 b4 12. d3 b3 13. Nd2 b2 14. h3 b1=N 15. h4 Na3 16. Rh2 Nb5 17. Ba3 Nd4 18. O-O-O Nf5 19. Re1 Ng3 20. Re3 Nf1 21. Rg3 g5 22. Ndf3 Nd2 23. Rg4 Nb1 [/pgn]
All you have to do is play ...b7-b5 in one move, and then h2-h4 in one move, and you've got it.
13 Oct 20
@greenpawn34
SOLV'D
8-move Rundlauf by bNb1, returning to the promotion square.
The composer is Unto Heinonen.