Caninoids

Men who become beasts is one of humanity's oldest nightmares.  And while we may be unsure as to whether or not such a transformation actually exists, there can be no doubt that people continue to report sightings of canine/human hybrid creatures.  These canid creatures are often found near where wilderness intersects with civilization, and are usually nearby water and expansive subterranean caves or tunnels.  Nobody can say whether caninoids are a separately-evolved canine species, human and canine hybrids, or some supernatural transformation brought on in humans by who-knows-what; but any of these explanations is likely cold comfort to those beset by the beasts.