# Don't Checkmate White!

Quite simply, find the one move by Black that doesn't checkmate White! It's really not that hard!

Good luck solving!

• Can I simply pass? Or forfeit? – Duck Jun 29 '19 at 1:12
• Starting with an en-passant capture isn't allowed unless there's definite proof (without reasoning from the assumption that a solution to the puzzle must exist) that the preceding move was a double pawn move. If you were to specifically lift this restriction, there would be two solutions: both dxc3(e.p.)+ and dxe3(e.p.)+ allow the white king to escape to c3 with non-checkmate continuations. – Bass Jun 29 '19 at 4:15

Perhaps the non-checkmating move is

dxc3 (e.p.) which allows Kxc3 in response,

but

it doesn't seem easy to prove that white's last move must have been c2-c4 making this possible.

• If we take the puzzle statement to imply rather than merely assuming that there actually is a move available that doesn't give checkmate, then we can deduce W's previous move and all is well. This would work better (at least for me) if it said something more like "Black has exactly one move that doesn't checkmate white. What is it?". – Gareth McCaughan Jun 29 '19 at 2:12

I think it is:

Move the b2 knight to d3. Then the white king is able to take the knight and not be checkmated.

• Ohh... didn't see that one – Duck Jun 29 '19 at 2:05