"...Child of dark! Herald of void!
First-created of the gods, or else their elder!
We know the truth: the world above the waves is nought but wan reflection of thy realm,
and we merely its fragile custodians.
O! Drown the world! Snuff out the stars!
We beseech thee, Great One, that all might hear thy song
Borne endless 'cross the sable deeps!"
- Extract from the Holy Book of the Water-folk, Chapter 27
So this is actually a redo of an old Dungeons & Drawings design that I did waaaaaaayy back in 2011! Go look at it if you want to see an example of the old slightly janky pixelart I used to do! I didn't think it was very good, even at the time, so I decided to redo it but still try and sort of... aim for the same feeling that I was going for before? If that makes sense? I think I succeeded to some extent.
I've always had a pretty deep-rooted fear of the sea, which I don't think is uncommon. I don't know if this was fuelled by anything (I suspect it was influenced by something I saw on TV or in a film) but I used to have a lot of nightmares about the sea, particularly tidal waves (like, cartoonishly large ones) and just the idea of big creatures either emerging or (sort of worse) lurking immediately underneath the surface. I actually went through a period of not wanting to do back-stroke at my swimming classes because I kept visualising something big "behind" me, under the water (yes, even in a swimming pool).
Krakens, Leviathans and other giant sea-creatures are likely to be encountered more as an environmental hazard than a traditional D&D fight, but I think their sheer scale makes them a fun (if terrifying) element to chuck into your game. I love giant monsters. I'm not, like, a big kaiju fan or anything like that, but I find there's something really compelling about a creature so big that it could destroy your life, your house, your city without even realising. Krakens also have the benefit of having a certain Lovecraftian mystique to them, emerging as they do from the inscrutable deep.
There's a persistent fringe theory about either octopi and/or squid being somehow descended from extraterrestrial life, and while I don't buy it myself, neither species does much to properly disprove it. They're pretty weird.