Since... 1994!

Help-mate in 4 moves

R. Smullyan

(White: Ka1, Rg7, Nb1, Nf8, Bb8, Bh8, a2, c2, c5, d3, e4, g3. Black: Ke5, Rf2, Rf4, a3, c3, c7, d4)

Help-mate in 4 moves

Solution