Great Cetaceans

The Great Cetaceans are a species of hyper-gigantic whale-like creatures who live in the deepest depths of the Atlantic Ocean, in the general vacinity of England. They are so large that they can have entire human-sized city-ish structures inside of them. (To give an idea of their scale, in the attached picture, the object in the upper right corner appears to be a regular-sized whale.)

Their bodies and intellects are so vast it is difficult for the aforementioned human-sized types to even communicate with them, requiring them to use interpreters recruited from the race of amphious "deepdweller" bipeds who live on the less-deep ocean floor, one of whom is evidently Trogulus the exchange student to the undersea dome of the Queen's Society. Despite this barrier, the Sparkish monster-expert Dimitri Vapnoople is reported to have somehow managed to "awaken" the Cetaceans and use them to attack Queen Albia's sunken kingdom.

One of the Cetaceans, called Ahnkokanth in "midsonic" language, is near the Society dome during Agatha and the mentally-diminished Vapnoople's eventful visit to it, and rescue-swallows one of Our Heroes' fleeing submarines when it gets caught in the blast as the dome Self Destructs. The sub's baffled inhabitants, sort of led by Hadrian Rakethorn, meet with the one of the interpreters, and (when he's not beating Rakethorn over the head with his staff of office) this individual and his assistants inform them that Ahnkokanth has lots of questions for them..Obviously, this sentiment is mutual.