He has 1,00's of the bloody things.
I saw this one once. N.Hoeg 1935
The stipulation is to add 10 White Rooks and Black checkmates in one move.
Setting up the mate in one was fairly easy.
I can do it with 6 Rooks.
But the condition is 10 Rooks. So....
There....how's about that?
The catch is, as with any problem, you must prove the position could have
happened with legal moves.
So it's 6 under promotions to Rooks and as Black still has all his pawns
all the pieces bar the Queen have been fed to the White pawns.
And if you look at that Black pawn structure you will see at one time it
must been something like this.
To let the newly promoted Rooks out.
The solution is
Black plays 1...Qxb4 mate.
All you have to do is show how it happened. I've tried it a few times without success.
But this to Swiss G is kid's stuff.