Shortest-proof-game challenge

Proof game in 27.0. EndgameEnthusiast will tell us how much shorter it needs to be.

@6289

Shorter:

This position was posted by EvinSung in the Illegal Position thread. I'm posting it here to see if someone can improve on the 50.5 move proof game I made for it.

@6291

What proof game?
Black has all 16 men, so white did not capture anything.
White has 15 men, only the h-pawn is missing. So black made 1 capture: the h-pawn.
Black has a doubled g-pawn g3/g7, so black must have captured ...hxg.
Black cannot have captured ...hxg when only the white h-pawn is missing.

EDIT:
Now I realise... black has captured some piece ...hxg and then the white h-pawn has promoted to replace said piece.

can you shorten this to 32.5 or less

Proof game in 32.5.

is it unique (both before and after 33.kc8

I suspect it's unique but it's hard to be sure.

You meant this position right?

from post 6522 in ipc

br h6 and wrong position

This position was posted by EvinSung in the Illegal Position thread, but there it was illegal because the black bishop at h3 was at g2.

How short a proof game can you make for this legal position?

Here's a proof game, refuting the illegality proof given a year and a half ago.

okay

Tricky proof game in 56.5. It shows why the version with the a2 pawn unmoved is illegal.

Here are some reasonable modifications to the common courtesy rules:

1. A position may be posted ending with a white move if the position is checkmate. Because checkmate means the game is over, and black couldn't make another move anyway. But when black is just in check, he has to make another move in a real game so it doesn't make sense for the position to not include blacks next move.

2. A game may also be posted if whites last move caused stalemate, dead position, or an insufficient mating material draw. The game is also over at that point so whose move it is isn't relevant at that point. It's a complete game, unlike where white moved and black can still move after making it a whole number of moves. BUT, the insufficient mating material position has to be reached on the last move. For example if whatever game construction being posted ends like this:

You can't end up in this position along the way:

Because the game ends at this point, so you can't reach a drawn position and then move the pieces around in a game thats already ended! Whites only valid last move in constructing the position would he a capture with the knight, this way White's last move actually ends the game and black can't make another move, so it's a full complete number of moves game.

Cool

I wonder if you ever have the urge to make a positive contribution to this thread, either by posting a possible shortest proof game for a position someone else has posted, or by posting your own position which presents a challenge in finding a proof game.