(last updated: 12/28/17)
They're otherwise called 'creatures of the night.'
The darkstalkers, as they might have become colloquialized through word of mouth and certain very bizarre internet forums, is actually a side term for a disparate collection of human beings afflicted by various metanatural phenomena. Oftentimes with bodies and spirits warped completely beyond recognition, many of these so-called 'monsters' represent a counterculture to today's sport fighting. They are routinely turned away from normal sport fighting events, shunned by the public and often in trouble with the government for their monstrous appearances and behavior.
Many who haven't relegated themselves to a hermetic life or various circus sideshow-level performance acts have only grown stronger, more determined, and more bold, gaining the attention of various powerful and avant-garde entities such as Shadaloo, Ultratech, and NESTS, all of whom seek to control the power of the Darkstalkers for themselves.
One of the strongest and most significant of these is the Romanian noble, Demetri Maximoff. A powerful nocturnal who has been at war with the Aensland family for ages, it is said that Demetri is a long-lived vampire who learned to hide his castle inside the light of the full moon. He gathers his strength, and continues to influence the Darkstalkers, in attempts to determine who will control the night.
See Darkstalkers Challenges for more information concerning this series.