Vivisector

Vivisectors were hollow aberrations that fed by removing organs from their victims to place inside their carapace.

Description
Vivisectors were gangly, bipedal insectoids that vaguely resembled a praying mantis. Their carapace was composed of dozens of dark blue chitin plates, and the cracks between those plates oozed blood and black ichor. The head had typical, multifaceted insect eyes, but lacked a mouth or nose. The wings were dark but translucent. Vivisectors stood about tall and weighed about.

Personality
Vivisectors were devoted to "feeding" their unnatural hunger, and were as methodical as they were malevolent.

Abilities
Vivisectors were strange, deadly creatures. Wholly deaf, they were immune to auditory effects and damage caused by sonic energy. They were naturally stealthy and, thrice each day, could become invisible for six seconds at a time. They had a sting with a weakness-inducing venom, and incredibly sharp claws.

Unnatural creatures that they were, vivisectors did not need to eat, drink, or breath; nor did they heal naturally. Instead, using their hideously sharp claws, they removed organs from still-living victims, somehow gaining sustenance from the organs.

Combat
Vivisectors were largely solitary cowards, preying on lone humanoids and attacking from hiding whenever possible. They used their talent for invisibility to avoid direct combat or to escape from superior forces. If forced to commit, however, a vivisector fought with a vicious, single-minded ferocity, ripping its foes apart with its claws, or crippling them with its sting.

Ecology
Vivisectors were feared and hated for their unnatural method of gaining sustenance, in which they removed living organs from humanoids, and placed said organs inside their hollow carapace. Somehow, they absorbed the essence of the innards, causing the physical organs to wither and decay- at which point the vivisector required new organs to live on.

Consequently, vivisectors made their homes in secluded lairs near plenty of potential prey, such as in sewers beneath cities or caves near a town. While not adversely effected by bright light, they did have an aversion to it, and typically were active during the dusk and night.

Vivisectors had a method of reproduction as bizarre as their way of feeding: they were asexual, and during the reproduction process an individual would gather organs from no less than ten different humanoids of medium size. They placed the organs inside their carapace as if feeding, but instead grew bloated over the two weeks during which their body process and transformed the organs; at the end of the two weeks the adult opened its carapace to release a single, smaller vivisector. The immature vivisector took only a week to grow to full size, at which time it left its parent's territory.

When a vivisector was killed, its carapace fell apart, spilling chitin plates and stolen organs across the ground in a reeking heap. Vivisectors had no definite lifespan, and as long as they had access to prey, could theoretically live forever.

Sometimes, groups of vivisectors gathered beneath large cities, working together to hunt prey. Such groups had a habit of gradually seeking out more and more powerfully individuals to harvest organs from; it was rumored that certain particularly ancient vivisectors could harvest the supernatural or magical abilities of their prey along with their organs, using them for a short time until the organs rotted away.

Vivisectors had no interest in most treasure, but were covetous of protective magical items, and a typical individual might have up to 2,300 gp worth of such treasures. They favored rings and potions, the latter of which they used by pouring directly into their carapace.

In the Underdark of Faerûn, all of the peoples that dwelt there feared vivisectors.

Rumors & Legends
Rumors claimed that there was a massive hive of vivisectors living beneath the Thunder Peaks, and that one of the monsters there had achieved great power and was summoning other vivisectors to its side for some awful purpose.