Family has long been of central importance to the God of War series, even before the latest entry made Kratos' relationship with his son a priority. It was the inadvertent murder of his own family that turned Kratos against his master, Ares, but the god of war is responsible for another loss even earlier in Kratos' life: that of his brother, Deimos. A misunderstood prophecy lead to Deimos' hatred of his own brother, a broken familial relationship that was explored in one of God of War's PlayStation Portable titles.
In Ghost of Sparta, which released for the PSP in 2010, it is revealed that a prophecy has foretold the demise of the Olympian gods. The Oracle has stated that their downfall will not be brought about by the Titans, but a mortal known only as the Marked Warrior. Although Kratos left some Greek gods alive in God of War before leaving for Midgard, it's clear that the Marked Warrior moniker refers to him. The gods, however, believed differently, which directly contributed to their slaughter at the hands of Kratos. Ghost of Sparta reveals that Kratos has a brother, Deimos, who Kratos believes was taken by the Olympians and killed at a young age.
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Deimos was born with an unusual, bright red birthmark, which ran over his left eye, along the top of his head, down his back, up the side of his chest, and circled around his left shoulder. Zeus and Ares believed Deimos was the prophesied Marked Warrior, the one who would eventually topple the Olympian pantheon. Deimos indeed had dreams of becoming a renowned Spartan warrior, and seemed poised to fulfill the prophecy. In an attempt to avoid their fate, Zeus and Ares devise to have Deimos captured. Ares interrupts a childhood
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