So decadent are these creatures that they fear equally the sun, the sea, dry land, and, indeed any surface not hewn by an intelligent hand.
Most prefer never to leave their half-drowned empire of Nephilidia. Inside its tarnished palaces and rotting halls they sit--forever knee-deep in black and stagnant water, with strange algaes stretched like
cobwebs from the surface to the once-ornate walls and crumbling statuary--endlessly elaborating cruel and languid intrigues, attended by salamander men and eyeless fish.
This amphibious species can change into a small, mobile pool of black blood, or take the form of a strange, darting, long-tendrilled aquatic animal resembling a hybrid of a lionfish and a manta ray. If reduced to zero hit points on land, the creature will revert to the former form. Consequently, if sufficiently injured, the Nephilidian vampire often sinks into the soil and becomes hopelessly trapped and intermingled with the earth. If grievously wounded in the water, this bizarre creature will turn into sixteen black stones and sink to the bottom. In either form, a drop of blood from another vampire is sufficient to revive the creature. Due to these vulnerabilites, the Nephilidian vampire prefers to travel via subterranian aquaducts, sewers, or other shallow, watertight, artificial constructions. They despise, but can--with an effort of will--tolerate clean running water.
In their humanoid form, they are distinguishable from ordinary vampires by the gills on their necks and their glassy blue eyes.