Illegal Position Contest!

Here's a repeat of my #4729 position from five days ago. I'm surprised nobody has posted a valid explanation of why it's illegal. It's not too difficult.

black has 13 pieces on board.

white requires 3 captures for the doubled pawns

the pawn a6

It is illegal because Black's g-pawn couldn't get over the the right!!!!

pawn h6

requires captures to get there

not available

white pawn on h6

its there

and making it illegal

this is a legal position

Also illegal because the coordinates are wrong, because h1 is a dark square, and a1 is a light square! (I just looked at a normal board)

watch:

in that case, the queenside pawns

they need too many captures

thats legal

um do you mean the pawn on h5 or h4?

and this is legal as white to move. nobody ever said black had to be able to castle.

Now you are on the right track.

Yes, easily legal. But we want to see illegal positions that look like they could be legal.

If you'd like to see it done in 20 moves instead of 29, here it is.

The other solution, in the next post after the problem was posted, used the bishop instead of the queen to lose a move. Both work equally well.

I'm not sure what the point of this one is. Your final position is the same as the position you had after move 1.

#4729 or # 4788, from n9531l1 : It is  illegal because: 1. Remaining white pawns have performed at least three captures to reach their current positions. [e.g. fxg, bxc, exd] This is legal for their are three black pieces missing 2. The seven black pawns from c-file up to h-file must have done at least seven captures of white pieces. This is legal as well, for their are seven white pieces missing [ e.g. gxh, fxg exf, dxexf, bxc, cxd ] So, all captured white pieces must have been taken by black pawns! 3. But one of these seven white pieces is a white pawn, and in case of the white a-pawn, then it was captured by a black b-pawn. But the black b-pawn captured to the c-file [see 2.], so the black a-pawn needed to capture an white piece number eight to reach the b-file first. But there are still nine white pieces... If it wasn't the white a-pawn which has been captured among the seven black captures, the white a-pawn has moved to the c-file by two captures, which totals then to at least four black pieces captured by white. But there are still thirteen black pieces .... So the position is illegal.  But probably there is shorter argumentation?