Nidhogg was paid 200 dinars by the warlord Otus to track down Hercules and Autolycus and retrieve the property they stole from the warlord's treasury. He followed the thieves up a giant beanstalk to Typhoon's cloud castle but was there eaten by the Cloud Serpent before he could execute his task.
- Nidhogg is the name of a dragon that gnaws on the roots of Yggdrasil, the world tree in Norse mythology.