Fenrir is one of the sons of Loki and Angrboda. Like his siblings, he has tremendous power and ferocious nature. And just like the others, he is special. Fenrir has the shape of a giant wolf but is able to communicate through the language of the gods. Since the day of which he was born, he has been growing stronger and bigger with each passing day.
He is certainly not the only famous monstrous wolf in Norse mythology. His children, whom he has conceived with a giantess, are (almost) as famous as their father. These are Sköll and Hati Hródvitnisson, the wolves that chase the sun and the moon high up in the sky. They are destined to be successful in their chase, signaling the start of Ragnarok.
Odin learns about Ragnarok and the violent future of Fenrir through a völva, when seeking out the prophecy about Baldr’s death. These events lead to the binding of Fenrir with a magical rope that is forged by dwarfs. In the end, he will escape during Ragnarok, after which he is the one to kill Odin in an epic battle on the fields of Vígrídr. He is slain by Vidar, son of Odin, in return.