[A straightforward, if depowered, conversion of the gnaw demon from the 4e Monster Manual 2. I wanted to make a CR 1 demon, since there aren’t any. ]
Demon, Mastikar This green, bloated imp is nearly
spherical, and its body is dominated by a toothy maw.
“gnawing demons” by some, mastikars are among the weakest of fiends. They are
not spawned from mortal souls in the same way as other demons, but instead form
from maggots and other vermin consuming demonic flesh. Maggots that feed on
demons become filled with a violent frenzy, feeding on each other as readily
as the carcass on which they grow. The victor or victors form leathery cocoons
the size of a human head, which hatch into mastikars. Thus, even a slain demon
can spawn further horrors.
for demons, mastikars are as common on the Material Plane as in the Abyss, if
not more so. They are most common in lands suffering from demonic incursions.
They are cowardly opportunists, killing and eating the weakest preferentially
and only attacking well armed and armored adventurers if cornered or if they
are distracted by fighting other monsters. Although they do not physically
require food, they are obsessed with consumption, tearing bodies to shreds and
eating until they cannot physically contain more meat.
A chaotic evil spellcaster of 5th level or higher can take a mastikar as a familiar using the Improved Familiar feat.
Of the sentient races that occupy the ocean, the merfolk are the most
numerous, or at least visible. Merfolk are as fascinated with humans as
humans are with them, most likely due to a physical resemblance combined
with the allure of foreign lower body. However, any closer relationship
between them is stymied by environmental requirements, though there are
many stories of individuals using magical means to overcome that
hurdle. Normally a marine race, freshwater variants have been sighted
living in especially large lakes.
But the mischievous and playful nature of the merfolk doesn’t mean that
they’re entirely harmless. Humans who abuse their waters or aren’t
careful with their nets will find their boats more likely to sink, or
suffer greater punishment as the merfolk appeal to their own watery
Yay, I got this done just in time for the end of Mermay!
There’s a lot of legends about mermaids, but not so many that I’ve found about mermen.
You get plenty of romances between fishy ladies and human men, but not
so much the other way around. The British Isles have a whole buncha
merfolk stories that mention the male half of the race, but while the
females are pretty, the males tend to be less attractive (a design trend
that continues to exist to this day). Think of it as the difference
between the Zoras and River Zoras in the Zelda games.