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The Problemist Supplement, 1996

#3
Symmetric Circe

1.Rd2!          (2.Sxe7  &            3.Re2#)

1...e6           2.Rd3               (3.Sfd6# )
                         exf5 [+wSc4] 3.Sd2,Scd6#
1...Sxf6 [+wPc3] 2.c4                (3.Re2#)
                         Sd5          3.Sf6#

White would like to guard d5 and threaten Rde1#, but 1.Sxe7? would bring a black pawn to d2, which stops the mate on e1. So, White plays 1.Rd2! to threaten the capture followed by a mate on e2. Black’s first defence is 1...e6, threatening the capture on f5 after which White plays 2.Rd3, guarding e3 and threatening 3.Sfd6#. If Black responds by capturing the knight, it re-appears on c4 and can then mate on either d2 or d6. Black's second defence is 1...Sxf6 (threatening 2...Sd5), which brings a white pawn to c3, after which White plays it to c4 (threatening 3.Re2#). This leads to 1...Sd5, after which White can mate by 3.Sf6#, the knight being invulnerable, as, if captured, it would be reborn at c3, checking the black king.