Section B1 – Min Win
1.Bd4!
( 1.Bc5? a1=Q! 2.Nb6+ Ka7 3.Nd5+ Ka6! 4.Nc7+ Ka5 5.b4+ Ka4 =, quiet )
1…a1=Q 2.Nb6+ Ka7 3.Nd5+ Ka6!
( 3…Ka8 4.Nc7# )
4.Nc7+! Ka5 5.b4+ Kxb4 6.Bxa1 +-
The key piece moves upon a square where it becomes the rear piece of two (Knight and Pawn) batteries activated each in turn. Composition inspired by L. Vidor
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