Four boys were playing a game in which they need to throw three stone in the water so that the stone at don't get sunk into the water(there is some solid area in water).
Boy1: Succeeded in throwing 2 stones at solid area but 1 of the stone sunk.
Boy3: All stones got sunk.
Boy4: None of the stones got sunk.
Boy2 was the winner but was struck by a stone in the head and died.
Who killed Boy2 ?
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Boy1, he was left with one stone.