Tunneling Nameless Thing

The Tunneling Nameless Thing had the appearance of a spiked and bladed Were-Worm. It was a spirit of Arda corrupted by Melkor during the Elder Days of Arda's making. Most of the Nameless corrupted by Melkor were placed deep in the earth to help mar the planet and serve Melkor himself. Most likely the elder Nameless were summoned to Utumno to help fight against the Valar. The Nameless that Gandalf and the Balrog saw, were most likely their descendants or lesser servants.