Ares was the Greek god of war, violence, and bloodlust. He represented the brutality of war in contrast to his half-sister Athena, who represented tactical warfare. Ares had affairs that resulted in children representing war-like concepts. In battle, Ares usually fought for the Trojans but switched sides when his son was killed fighting for the Greeks. Mars was the Roman equivalent of Ares, seen as a defender and representing war as a means to peace.