In Norse mythology, the serpent Jörmungandr was the son of Loki, god of mischief, and the giant female Angrboda.
The Jörmungandr resided in Æsir, the Norse pantheon. But he was banished from that land by Odin, king of the gods, and sent to dwell in the sea that encircled the mortal world of Midgard.
It was of course expected that the sea would drown the Jörmungandr. This was not to be the case however; instead, the Jörmungandr began to consume the ocean waves.
The next time he was spotted, the Jörmungandr had grown so huge that he was now capable of encircling the entire planet and reach its own tail..
The Vánagandr or "fen-dweller." A monstrous Wolf in Norse Lore.
Odin and Fenris (1909) by Dorothy Hardy
Fenrir the Wolf is the father of the wolves Sköll & Hati Hróðvitnisson, and is a son of Loki, and is foretold to kill the god Odin during the events of Ragnarök.