Four kids having five rocks each were playing a game in which they need to throw the rock at solid area in the water.
Kid1: Succeeded in throwing three rocks at solid area but one of the rock sunk.
Kid3: His aim was so bad that all rocks got sunk.
Kid4: He was awesome and none of the rocks got sunk.
Kid2 was the winner but was struck by a rock in the head and died.
Who killed Kid2 ?