Anticipatory half-pin
The black king steps to the half-pin line after one of the black pieces has vacated the line. Two reciprocal anticipatory indirect self-pins are required.
See also: Half-pin; Anticipatory self-pin.
Janevski, Zhivko
Die Schwalbe, 1985
4th Prize
h#2 b) bPe6→d6
(7+9)
a) 1.Bb8
Rc6+
2.Kb5
c4#
b) 1.Bg8
Bc6
2.Kc5
Bf2#