I've been working on this on and off and I can never get past one hurdle. The stip is white to play and not mate in 2. Assuming an eventual position where the black king cannot move, then I quite like the fact that in the above left hand side of the board, the king cannot move because check can only be blocked with the queen which in turn has to be taken checkmate, and same with the pawn push.
As for the right hand side I've been trying things resembling this:
(though obviously not that, it's just an example) though they all have nasty mates in 1, which I'm trying to avoid, or not very nice solutions. I was thinking the key could play on diagonal queen captures but it's difficult to keep that diagonal open... ah well.
Please help 🙂
every move should lead to a mate in two (not necessarily by queen capture) apart from one. Your suggestion does fit what I'm aiming for, but isn't especially nice... I've been working on this for quite a while this weekend and still go nothing too nice. It must be possible.