BDS
Problem Observer, 1994
#2
LEO g4
PAOs b4; c3
VAO h5
1.LEf5! (2.Rg4#) 1...Kxf3 2.PAf4# 1...PAxf3 2.Bd4# 1...Rxf3 2.Bc4#
The key gives the black king a flight, and, after the bK takes it, he is mated on the square he just departed from. Two other captures on f3 lead to two more anti-battery mates.
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