Jörg Kuhlmann & BDS
StrateGems, 1999
SEMI-R#2
Köko
Circé
1.Sc6! () 1...Rb8 2.Bg5 Rxb2[+wRa1]# 1...Rd8 2.Rbb8 Rxd2[+wBc1]#
After 1...Rb8 it is clear that Black will mate by 2...Rxb2[+wRa1]. Although b2 is not adjacent to another unit, it is after the captured wR is reborn on a1. The same adjacency applies after 1...Rd8, when the mate is 2.Rxd2[+wBc1]. In the first variation the wB has to get out of the way. 2.Bc3 and 2.Bc1 are clearly not on as the mate is defeated by 3.Bxb2[+bRh8] while 2.Ba5 is check to the bK. After 1...Rd8 the wRb2 has to get out of the way. Only moves up the file are legal and do this, but all except 2.Rb8 are check to the bK.
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