And the OP "puzzle" isn't even a win for white...
"I challenge you to give me a puzzle... oh, but I don't know how back rank mates work"
This doesn't make sense, you end up with a rook on d8 against the black king on b8, it can't move pawns, I don't see why it's not a win for white.
After 1.Qe8 what is every legal move black has?
I believe that the only legal move would be to resign
?
This is like a 200-rated puzzle. Black to play:
Now White can resign, yes.
(I'm guessing that was the joke ...)
And the OP "puzzle" isn't even a win for white...
"I challenge you to give me a puzzle... oh, but I don't know how back rank mates work"
This doesn't make sense, you end up with a rook on d8 against the black king on b8, it can't move pawns, I don't see why it's not a win for white.
After 1.Qe8 what is every legal move black has?
I believe that the only legal move would be to resign