Ghoul whale

A ghoul whale is a creature mentioned in the Commonwealth.

Background
An aquatic creature, described as "dark and ominous" living in the ocean off the Boston Harbor.

Characteristics
In a conversation between two caravan guards in Bunker Hill, one tells the tale of her grandpappy seeing a ghoul whale named Ol' Peg while gathering mirelurk eggs on the beach. The guard describes the creature as being one of many ravaged by radiation, having grown massive in size, creating a tremendous clamoring sound as it emerged from the ocean, causing her grandfather to flee. She encourages the other caravan guard to ask any of the old timers, who will agree that "something ancient and terrifying haunts the sea."

Appearances
A ghoul whale is mentioned in Fallout 4.