A primordial spirit of darkness in spider form, Ungoliant's origins are obscure. She may have been a Maia corrupted by Morgoth, or she may be something older and stranger. She dwelt in Avathar, in the shadow of the Pelori mountains, and Morgoth sought her out as an ally in his assault on Valinor. Together they destroyed the Two Trees of Valinor, Ungoliant devouring their light and growing to monstrous size. She then demanded that Morgoth surrender the Silmarils to her, and when he refused, she attacked him. Only the arrival of his Balrogs saved Morgoth from being consumed. Ungoliant fled south to Beleriand, where she mated with the great spiders there and eventually, according to legend, devoured herself in her insatiable hunger. Shelob of Cirith Ungol was the greatest of her offspring.