Wrack Mephit

One of the most dangerous and loathed creatures to emerge from the manifest chaos of the wrack are the wrack mephits, sometimes simply called "trappers." This is because although no more dangerous in single combat than many other monsters, wrack mephits combine their elemental shaping abilities with cruel dispositions to spend most of their time creating traps or pitfalls to humiliate, injure or murder those unlucky enough to wander near the mephit's territory.
Able to transmute matter into a variety of basic elements and reshape it, wrack mephits will create a wide variety of deadly devices and pitfalls purely to satisfy their own sadistic amusement. More than one adventurer passing through a location that couldn't possibly be the site of a booby trap has fallen prey to the machinations of a wrack mephit.
While capable of creating many traps, wrack mephits seem to instinctively understand that too many traps leads visitors to be on constant guard, so rather than blanketing an area, they usually place just a handful in key locations and then watch from the shadows when others come near. Capturing a wrack mephit in a magic circle can make exploring a dungeon significantly safer, as in order to obtain their freedom, many mephits will trade the location and nature of their constructs (but no one else's) and a promise to cease mischief.

Basic Information

Genetics and Reproduction

Mephits are almost always born from wrack energy, but in cases where they find especially fertile hunting grounds (see below) a mephit will sometimes divide into a small "family" of mephits. These groups are especially dangerous because mephits that share a common parent don't seem to have any issue with working together. An explorer who thinks themselves safe after catching or killing one mephit may find that they've merely attracted the attention (and ire) of several others.

Growth Rate & Stages

Mephits tend to grow in size proportional to the scope of territory they cover and the number of interactions they have with prey. This has led some scholars to suggest that the Mephits may literally feed on chaos and/or fear, getting stronger as more fall victim to their wicked designs.

Ecology and Habitats

Wrack mephits are typically born near a wrack field (see below), but once made they will travel far and wide in search of a suitable lair. Once established in said lair, mephits are very territorial, and it's not unknown for them to plot against one another to claim particularly desirable territory (in this case, desirable meaning frequently visited by people who the mephit can maim and torment with minimal personal risk). Such territorial disputes have even led to (temporary) alliances with adventurers or explorers. Mephits also appreciate things that they can't find in their habitat as gifts, and will sometimes grant safe passage to someone who provides them tools to make their next visitors life even more miserable.

Dietary Needs and Habits

It's unclear whether wrack mephits literally feed upon the fear, misery and pain they inflict with their horrifying devices or if they simply are born sadists en masse. Some have theorized that either residual wrack energy or deposits of elemental energy are responsible for "feeding" the creatures, but little is known for certain.

Biological Cycle

Mephits seem to emerge from areas where large concentrations of some elemental substance interact with wrack energy, the reality-twisting chaos of that phenomenon twisting the natural world into a vindictive enemy of all living things. These "Wrack Fields" can draw their energy from the longstanding distortion in the Eastern parts of the continent, passing Wrack storms or even chunks of meteorite or volcanic rock that have been displaced from areas of highly concentrated energy.

Additional Information

Domestication

While actual domestication has proven impossible, certain extremely powerful magic users and alchemists have reportedly found ways to control and/or bribe wrack mephits. As creatures infused with wrack energy, they're much more difficult to control via magic than their strength might otherwise suggest. Even under some amount of control, the creatures still refuse to act against their nature, but they can be charged with trapping specific areas and creating bypasses for their "masters" provided they get to watch the ensuing misery from a safe distance. That said, many mephits see a special irony in murdering those who believe they have the creatures tamed, so many periods of "domesticity" for wrack mephits are cut artificially short.

Average Intelligence

Wrack mephits generally display the intelligence and demeanor of a psychopathic 12 year old. Their intuitive grasp of engineering and trap mechanics is at a genius level, however, leading some to speculate that they may be the physical manifestations of some malevolent will bent towards creating suffering.

Perception and Sensory Capabilities

Wrack mephits seem to have an intuitive, almost inborn understanding of minerals, chemicals and certain mystical phenomenon. Just by sight and smell, most mephits can identify substances, including alchemical substances and some potions and poisons. This makes them extremely dangerous with even limited tools.

Origin/Ancestry

Disputed: Some allege they are dark fey, while others believe them corrupted elementals. The only thing everyone agrees on is that they're corrupted by the Wrack.

Conservation Status

Wrack mephits are at the top of everyone's list of species that OUGHT to be extinct, but that's not likely to happen anytime soon. They've survived and thrived everywhere civilization isn't by avoiding settled areas and using their speed, flight and knowledge of local terrain to evade anyone who tries to challenge them to a fair fight.