 According to Zeratul, Kerrigan factors prominently into a Xel'Nagan prophecy concerning the Zerg, the Protoss, and the Hybrids.Heart of the Swarm reveals that Kerrigan is the only being powerful enough to stop the fallen Xel'naga Amon, though exactly how is not revealed.Though originally intended as a throwaway character, Kerrigan grew on the developers, who gave her a greater role in the series.