Shortest-proof-game challenge

Proof game in 9.0.

Unique SPG in 39.5. New record.

This was quite nice to solve. 3 white Schnoebelen pieces in this proof game:

It seems that anything I make on this theme is cooked. Unless Rh4–>g4 is unique, I might have to abandon this idea too.

Solution #1 :
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 1. Pf2-f4 Pb7-b5 2. Pf4-f5 Pb5-b4 3. Pf5-f6 Pb4-b3
 4. Pf6xe7 Pb3xa2 5. Pe7xd8=B Pa2xb1=B 6. Ra1-a4 Bf8-d6
 7. Ra4-g4 Bd6xh2 8. Pe2-e4 Pd7-d6 9. Bf1-a6 Bc8-d7
10. Pd2-d3 Bd7-a4 11. Bc1-d2 Ke8-d7 12. Bd2-a5 Kd7-c6
13. Ke1-d2 Nb8-d7 14. Kd2-c1 Ra8xd8 15. Kc1xb1

Result:
Unique solution
2.57 seconds

Finally! I have made a unique proof game with the double-side Schnoebelen theme, just when I was losing hope. Thank you (and n9531l1) for testing these positions; now I am finally content with this position. That was a tough composition task!

I’ll just post the position here for people to see:

#6481

Switch backs by Q, N and 2x R.

I'm brand new to this, but here's my shot at #6491

The next two moves are Kh8 and b8=R, but the king move is not legal, so I can't do it in analysis.

edit: I now realize that an illegal move should not be in a game proof, so in the beginning, black's b pawn should take white's b pawn after the a pawn, and white's rook should take black's b pawn afterward and then hang around until the end. This proof will probably be 1-2 moves shorter, but I'm too lazy to find out

You found the unique SPG for this position composed by Michel Caillaud.

Proof game in 13.0.

Good work, a unique proof game with both sides having a single Schnoebelen bishop. Here's a position that does the same thing with rooks.

See how short a proof game you can find for this position, being careful not to reach a dead position prematurely.

KxBf1

33.5 is very good. Can anyone make it shorter?

First try, 11.5