Manifestations
Not everything can exist in normal reality–the place they come from is just too different. In that case, they appear as a manifestation, which is able to function in our reality. Manifestations are varied in form and function, but the result is always the same: killing the manifestation does not and cannot harm the original, though they do tend to avoid the places where their manifestations were slain.
Entities
Entities are living, or quasi-living, things that do not seem to follow the normal rules of life: they seldom reproduce, often do not eat, and may be completely incorporeal. Their unpredictable appearance, behavior, and interactions make them by far the most dangerous supernatural creatures that can be encountered.
Beings
Sentient creatures that are roughly equivalent to humans in terms of intelligence and temperament but choose to remain aloof, hidden, or otherwise disengaged from human affairs. This includes those few who live among or are able to pass for human as well as others who disdain contact but are able to communicate. Beings have far more to fear from humans than vice-versa, though in a one-on-one scuffle any given being ill often have the upper hand.
Beasts
Much like beings, beasts are of roughly animal intelligence and behavior, albeit with unusual properties or characteristics that defy known laws of physics and/or zoology. Unlike beings, they are usually unable to intelligently communicate, though peaceful interactions are sometimes possible.
Spirits
Spirits include any creature that was formerly alive and has continued to display signs of life after death. This goes not seem to prevent them from dying a second time, or at least being destroyed, and even incorporeal spirits leave traces of their passage.
Hybrids
The aforementioned categories can all exist as hybrids as well; since the laws of physics do not seem to apply in some cases, the laws of reproduction do not seem to either. As such, it is common to find humans, animals, and even plants that have mixed roots. The results can be unpredictable, to say the least.
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