Entropy

When Ao banished the primordials to Abeir he imprisoned Entropy in the form of a sphere of annihilation and placed him on Toril as a warning to the gods that they faced annihilation if they did not behave. With Mystra's death and the subsequent Spellplague, Entropy was freed from his prison and grows stronger, threatening to devour the universe. He is worshiped in Chessenta by the Cult of Entropy and currently dwells in the Maw of the God Swallower in southern Chessenta.