Is this position legal?

You guys got it. This was my own composition .

Is this legal? (Board is not upside down and I don't know the answer myself)

No. Black has eight pawns, but they are all above the a8-h1 diagonal, so none of them are in a legal position for the a-pawn or b-pawn.

It's legal.

Nice!

Well, nice of you to change the question so it looks like I'm clueless.

Sorry GBog I noticed that I posted the wrong question just after you commented.

Just curious, what was the original problem?

I guess there are Black pawns on h6/h5/h4/h3.

Well. Original problem was a bit wrong. Here is that problem if you wish.

Here's something to try.

#1285: this one is clearly illegal. Pawns can move forward in a straight line or in a diagonal. Therefor can they never end behind their diagonal. For instance: the pawn on a7 can walk to b6, c5, d4, e3 etc, but will never be able to end on e4 or d5 or f6. If you take a look at the black pawns, then do you see that there are eight pawns and all pawns are behind the diagonal of the black a-pawn. Therefor can the position not be legal.

#1286: this is a legal mate, that most likely will never occur in a game. White has made 10 captures with the pawns and black is more than 10 pieces missing. The pawns are 'behind the diagonals' as I explained above. Conclusion: legal.

i think theretically it is leagal but very unlikly

Better than 1.f3, at least :P

#1285 is illegal. I know that, that's why I told it as wrong puzzle. Well, can anyone come up with a proof game for #1286?

Inefficient yet trivial construction. Probably could shorten if I started with a plan rather than just moving stuff.

I know I'm just a senile retiree, but I don't understand why people construct proof games for positions like this. Why not just say that last move is 0...Nf3+ and white's required 10 pawn captures are more than balanced by black's 14 missing units?

To convince people that are not retro enthusiasts. Just like how you should explain (why this line is winning etc) more clearly to people new at chess than to masters.

I prefer to raise the bar immediately. Anyone who cannot understand the idea of pawn captures balanced by missing units from a simple sentence is not worth the teaching time.

chaotic_iak wrote:

To convince people that are not retro enthusiasts. Just like how you should explain (why this line is winning etc) more clearly to people new at chess than to masters.