Castling vertically problem I've once saw a joke chess study about castling vertically. However, I have forgotten who has composed it. I remember that in the positions, all the pawns were locked, but not much else. Does anybody know who was the composer of this problem?
I believe this is the position with White to mate in 3:
[FEN &quot;8/8/4P3/3p4/2p3p1/1pP1kPPp/1P5P/R3K2R w KQkq - 0 1&quot;]

Tim Krabbé and Max Pam exploited a loophole in the rules when they composed this problem in 1972.
There are 3 variations depending on Black's responses with the third variation being vertical castling.

1.e7 Kd3 2.e8=R gxf3 3.0-0-0#.
1.e7 Kxf3 2.e8=R d4 3.0-0#.
1.e7 Kxf3 2.e8=R Kg2 3.0-0-0-0#!.