Illegal Position Contest!

Obviously illegal. Three pawns in the triangle a2-a3-b2.

Here's an obviously illegal pawn position. Six pawns in the triangle a2-a6-e2. Move any of the pawns to any square in that triangle--still illegal.

Legal:

We discussed basically the same thing:

For some reason, I can't post diagrams.

What worked for me is to insert the board and click on Post, Edit, Post.

Thanks. There it is.

#5759
It is legal: fxe6++ e.p.

But how will the bishop on b1 give check previously?

It's almost no different from this:

EDIT: Never mind, forgot the king could have allowed a discovered check by the bishop

EDIT2: I realised that even this is not possible, so it's probably illegal.

#5761

It is legal:
White king at b2, white bishop at a1. Black plays ...b4xa3++, then Ka2+, then ....e5, then fxe6++ e.p.

True, but you haven't answered the real question. Why was it posted in the Illegal Position thread? We'll never know unless EvinSung tells us.

I wouldn't call them basically the same thing. The position you posted (#5753) is illegal, but becomes legal if the white pawn at a2 is replaced with a black pawn. The new position (#5751) is legal to begin with.

#5751
Proof game

Nice.

Prove that this position with white to move is illegal:

#5769
Black has promoted 4 dark square bishops and 2 queens. Black must have captured 3 white pawns to get past them to promote 6 pawns. The last move must have been ...Bxf6+. Thus 3 + 1 = 4 white men must be captured. White has 13 men and thus only 3 can be captured.