Thunderdell (Welsh: Taranau), also recorded as Thunderdel, Thunderel, Thundrel, Thunderdale, or Thunderbore, was a two-headed giant of Cornwall slain by Jack the Giant-Killer in the stories of Tabart and others.[1]
Jeff Rovin's The Encyclopedia of Monsters (New York: Facts on File, 1989) misspells Thunderdell as "Thunderel", and after describing him, proceeds to tell the basic story of "Jack and the Beanstalk" with no further mention of "Thunderel", despite being the title of the entry. He then refers readers to Cormoran.
Appearance
In Jack the Giant Killer, Thunderdell first appeared where he crashed a banquet that was prepared for Jack. During this time, he chanted "fee fau fum." Jack defeats and beheads the two-headed giant with a trick involving the house's moat and drawbridge.
According to one version of the story from 1800, Thunderdell (here identified as "Thunderful") hails from the North Pole. He attacks Jack's banquet in order to avenge the deaths of two giants he had earlier slain, but is himself defeated and his heads sent to the court of King Arthur.
^Bushnell, Adam (27 August 2022). "Jack the Giant Killer". Misplaced Myths and Lost Legends: Model Texts and Teaching Activities for Primary Writing. Sage Publications UK. pp. 87, 89. ISBN978-1-5297-9157-0.