Gormungandr, Serpent of Arreat is a unique Rockworm (of Demonic Serpent subtype) that can spawn in Arreat Crater Level 1 in Act III of Diablo III.
It has the Frozen Pulse, Frozen and Plagued affixes.
Trivia[]
The name of the creature is a reference to the World Serpent Jörmungandr in Norse mythology.