The reference to a sub extinction asteroid that struck the world of Greyhawke in 96,000 BE.
The asteroid struck the old Elven Capital of Calaborleen. A city of crystal spires and haunting beauty the location of the Archive of the Illurvin. The destruction is complete. The dead are never counted or truly known. The land is twisted and burned.
The Human cultures of the day blame their own gods and destroy what is left of their own cultures the end of the Maztka Culture.
A tender sapling is found sheltered by a large rock. This will become the Great Mother Tree. A primal being in its own right. The rock is venerated as the heart of Anadolintor. The three eventually grows into the Great Mother Tree.
History on Greyhawke is divided in to two periods, pre Holocaust and post Holocaust.