Our campaign setting has a storied relationship with infernal entities. The Folly was created by a wizard with the help of his three demonic lieutenants, and since then demons and devils have had a strong presence in five out of six campaigns within that setting. One of those lieutenants in particular has been villain, comrade, and adoptive parent to the parties in various seasons. We discovered in season 5 that she’s also the generative force that created the hundreds of mephits – those elemental imps made most infamous by the Planescape setting – who have populated the Folly over the centuries. Since these mephits arise from the material of the Folly’s demiplane, they are native beings rather than elemental outsiders.
Early in the history of the Folly, mephits served as workers in the infernal bureaucracy that governed the world. They were town guards, construction workers, office grunts, and technical staff. Because of their role as the workhorses and face of the demonic regime, mephits were quickly marginalized and scattered into the wilderness when the deities succeeded in toppling the demons from their thrones. Hunting mephits became sport for some of the more unsavory residents of the Folly. Long after the history of the world was lost to all but a few dusty tomes, mephits still carried a reputation of being shiftless, parasitic, evil nuisances.
Mostly, mephits are content so long as they have an elementally appropriate environment and shelter from physical threat. Mephits settle comfortably in extreme niches which are not often filled by other beings, and they draw sustenance directly from their governing elements. Since they are not driven by shared purpose such as finding food and shelter, they are not given to forming long-term social bonds. Mephits will band together to fight a common enemy, but otherwise they do not think in terms of community. Still, most mephits prefer the company of others. If you find one mephit, there is probably a group or colony nearby. They are perfectly capable of working together toward a single goal, even if doing so is not the basis for the way that they relate to others.
What mephits as a class value most is comfort. For some mephits this means spending all day lounging in an armchair (magma pool, acid bath, glacial stream). Other mephits find comfort in personal security. They might seek employment with a more powerful entity, like an experienced wizard or a government agency. A few mephits have access to magic which allows them to disguise themselves or change their form, allowing them to integrate into the towns and cultures of other clannad.
Even though mephits adore comfort, they also enjoy new experiences. Most mephits have a touch of wanderlust which arises every so often. Mephits move in and out of colonies and uncharted territories alike with regularity. Adventuring is an unusual pursuit for a mephit, but it is not unknown. A mephit with a taste for dangerous living might be more likely to join (or found) a bandit group, relying on safety in numbers if a shakedown goes sour. Most bandits don’t have the resources of an adventuring party, however, and adventurers are more likely to take risks to keep each other intact.
Mephits do not have a “normal” lifespan. They arise from the environment and coalesce as a natural event. Some mephits live for a few centuries. Others return to their environment for no understandable reason (perhaps giving in to the comfort of basking in their constituent materials). They are generally immune to disease, and their fast healing quality means that – with the right precautions – injury is rarely permanent. Since the generative event which creates mephits on the Folly sent ripples outward through time in a non-linear fashion, mephits are only loosely linked to chronological passage; they are simply solutions to wave functions which might appear or disappear at the whim of space and time.
The relationship between mephits and religion is interesting indeed. Mephits recognize their demonic mother, and they acknowledge the existence of the deities. Beyond that, any relationship with the divine is entirely personal and usually fraught.