 The Librarian queries an elder, Glow-of-Old-Suns about the origins of her people and is taken to a valley where she learns that the history of the natives is contained within a vast growth of moss - an organic Domain.By accessing this information reserve, she would learn that Warriors drove the Precursors to Path Kethona during the Forerunners' genocidal campaign against their creators ten million years earlier, and that the planet's inhabitants were descendants of Forerunners exiled there as punishment for refusing to partake in the destruction of the Precursors.Back in the present, the Ur-Didact emerges from a stasis-bubble on a broken-down Builder hulk drifting in a Burn, the designation for a Flood infected star system.