Before Final Fantasy turned Bahamut into a dragon, it was a fish
Vastids - man-maimers who live in contaminated water areas and Balrin Algae.
In the dark one morning, the Bloated Black Beast slowly rose to the water's surface. Whence it crested, great gouts of flame erupted from its Misshapen Form and were hurled hundreds of feet in all directions. It dove again, and appeared as nothing more than an Inky Shadow of Malice. With no purpose, It swam on; occasionally cresting and flaming, but still without purpose.
This sea monster seeks to devour more than just mere flesh..
"Greetings, Mortal," Said the bubbly, hissing voice in his head… What the hell was that, he thought. "Not hell, the Ocean. Walk into the surf, my child. I will protect you."
She rose from the waters and cast her eyes across us. I dropped my spear, and the man who was moments before intent on my death did the same, letting his sword and shield fall to the sand at our feet. Let it not be said that the gods do not care for the deeds of men, nay they do care. And in our bloody case, they dissapproved.
Canst thou draw out leviathan with an hook?
Canst thou fill his skin with barbed irons?
or his head with fish spears?
Have a family that is ever at odds with each other? Beware lest the Slurran comes for you..
The Flowing Death is one of the most feared monsters in all of Vallermoore’s rivers and ocean, not because of the numbers of people it has killed directly, but because of the semi-starvation it’s visits bring, and because it cannot be seen until it attacks it’s prey.
Teenagers who run away from home to live in the wilderness may become feral. As they become more and more feral, they gain some supernatural powers (a la Peter Pan - ability to fly, things they imagine come true - possibly quite powerful), but at the expense of their humanity and ability to speak, comprehend complex subjects, etc. Maybe they have a leader: the most feral of them all.
A regression into a fantasy childlike state.