A problem which was contributed as an original for the World Chess
Solving Championship of 1994. The helpmate round consisted of three
problems (the others being a three-solution h#2 and a single solution
h#5) to be solved in 50 minutes, so to solve under WCSC conditions give
yourself 20 minutes.
1.Sxc2 Sxe3 2.Sd4 Sc2 3.Qb5 cxd4 and 1.Rxg4 Rh2 2.Bb5 Rh4 3.Rb4 cxb4.
A problem which displays a number of unifying features without the solutions matching exactly. The white piece captured in one solution supports the mating pawn in the other, while the black capturer is itself captured on the mating move. The black queen and bishop take turns to block b5.
Richard Stein: Sparkling clear role-switches of the knights and rooks, with toggling pawn mates to boot.