Peace reigns until Chaos appears, the people fight back, but ultimately fail. He awakens various gods, some who were mortals previously - Teclis, Tyrion, Alarielle, Nagash, Gorkamorka, and a few others. Sigmar travels the mortal realms, uniting the human tribes. Dracothion and Sigmar take all the souls trapped with the old world and revive them into the Mortal Realms. He finds Sigmar, revives him, and shows him the Realm Gates.
Dracothion sees the core of the planet, and chases it, to admire it for eternity. End Times happened, ultimately the entire world was destroyed, it's crust ripped off and sent hurtling through space with an unconscious Sigmar in tow. I actually kept searching and found a post somewhere else which partially answers my question.