Second World

Many religious texts describe it as a separate world that was destroyed before the creation of Yerth, the Third World.
By all accounts, the Second World was a paradise for mortals created by the gods. It was watched over by Grunnush from the Palace of the Gods .
While this world lasted, the mortals prospered. Eventually, the world descended into war and Chaos, and was brought to an end when Grunnush fell.

Summary

It is said when Grunnush fell, he created the massive Inland Ocean.