Your Dishonored whale post made me realize something. They're clearly carnivorous, the more or less Dishonored universe's equivalent to our Sperm whales (in more ways than one) so that begs the question, just WHAT do they hunt? And how BIG does that prey get to sustain the caloric intake an animal of that size would need? Especially considering Sperm whale's main source of deep sea prey, Giant squids, can grow from anywhere from 30 to 50 feet in length. With unconfirmed specimens suspected of growing even larger than that, the mind boggles!
Did a quick ctrl+f for assorted words (kraken, squid, whale etc.) in my DH text dump and found no mention of whales eating anything, ever. So who knows, maybe they don't eat at all!
We do know they have intestines at least, see "e" in this diagram.
Canonically they actually have teeth and baleen, meaning that they could filter feed if they so choose. (An excerpt from the book "Whale Vivesection" says they have "row upon row of teeth and a baleen running along the upper jaw. Through this broom-like structure, I assume she filtered food from the water that was too small to be chewed.") Obviously they'd have to take in incredible amounts of plankton if they wanted to sustain themselves solely by filter feeding but it is, theoretically, an option - and we don't know just how large and deep the oceans are. Might be lotsa space for a shitton of plankton in there idk
And I do think that Super Giant Squid (TM) are deffo at least possible to exist in DH - they certainly do feature in legends. The globes show one large enough to take down a ship - this is obviously just a copy of "Le Poulpe Colossal" by malacologist Pierre Dénys de Montfort, 1801, so this Kraken would be the same size as the Kraken legends in our world, but maybe there's even bigger ones out there!
and then there's also the Serkonan "Old Sea Beast", which is called "Kraken" in the files. This guy kind of freaks me out because I can't tell how big he's supposed to be and also where his face and eyes and stuff are, he looks like he's as tall as a mountain and that's just Too Big - though that'd make him the perfect family dinner for a herd of Leviathans.
As much as a copout it is I do actually feel like they're at least partially magic, with their connection to the Void, and as such can be at least partially sustained by magic in some form. Clearly they're also very real, physical animals, with families and death throes and blood and guts and bones, but they're also magic enough that I do think if you just let a Leviathan be it will simply continue to Be, whether it can feed or not (though that state of continued existence is easily disrupted by human intervention).
