Changelings

Changelings are a peculiar Species, quite unlike any other. They are extremely rare, and their origins are uncertain. Many Changelings live within Humanoid societies, masking themselves, as few outside their own species seem willing to trust them. Others make their livings in isolated communities in the wilds, or even on their own.

Description
Changelings, by their nature, seem to defy any meaningful description. In their inert state, they appear to be little more than a puddle of a semi-translucent gelatin-like substance, similar to an Ooze. Despite the apparent similarity, however, Changelings are notably different in a variety of ways. For one, their form is much more cohesive than that of Ooze. The material that makes up their bodies is fluid and can be shaped at the Changeling's will, but it is also capable of stiffening, to form a tough outer membrane, and even a bone-like structure that allows these otherwise amorphous creatures to appear convincingly as a member of another species. Throughout their lives, most Changelings appear to be a member of another species, and have the ability to change their physical appearance at will. An individual Changeling may look like an Orc one day, and an  Elf the next, or even a Drake. Despite this, Changelings do not seem capable of properly replicate the sense of sight possessed by most other sapient species. Their bodies appear capable of interpreting the external stimuli of scent, and sound, and taste, but sight eludes them. The best they can do is to rely upon their other senses to approximate the positions within a small radius around them.

The deception of a Changeling is dependent upon the individual's own skill in manipulating their own body. For many, the imitation of another species runs only skin deep. A wound that punctures the Changeling's body would reveal their nature. For a select few, mastery of their body's shape-changing capabilities allows them to imitate the internal structures of another species' body as well, although some familiarity with the species is necessary for such thorough deception, and very few Changelings are familiar with the internal organs of other sapient species. Most Changelings are capable of maintaining their adopted form through normal circumstances. Even while resting, most are capable of keeping their bodies in the shape of their choosing. Extraordinary circumstances however -situations that might shock a Changeling, or otherwise break its concentration- might cause a Changeling to temporarily morph their bodies in ways that they did not consciously intend to.

Deception is Survival
Many Changelings dwell in small family units within a larger society of Humanoids, adopting the appearance of a member of another species, and pretending for all the world that they belong. Many cultures throughout history have viewed Changelings in particular with an air of distrust at best. In many places of the world, if a Changeling is found out, they risk being run out of their home, or even hunted and killed out of fear. For this reason, Changelings tend to hide out when present in a larger society that is not their own. They tend to avoid confrontation, and blend in as well as they can.

For many, a natural way to avoid being found out is simply to always be on the move. These migrating bands of Changelings often make their way as travelling performers or wandering minstrels, never staying in one place long enough to be identified. Occasionally, Changelings have made settlements all their own, just outside the confines of other societies. These communes are generally walled-off, with only a few members leaving the place at a time for food or water. Some of these communes even masquerade themselves as monasteries or nunneries as an easy way to excuse cloistering themselves away from others.