Lycanthropy

Lycanthropy was a disease (for afflicted lycanthropes [ ]) and a hereditary condition (for natural lycanthropes)  that caused humanoids and giants to change form, usually into a hybrid humanoid-animal state. A lycanthrope, also known as a werebeast or a weretype, was an individual who possessed this condition. They were called "nightwalkers" by some.

Society
Some lycanthropes were in control of their ability to transform and others were not. Most lycanthropes had some empathy with animals with which they shared their forms. Most lycanthropes were humans or elves, but orc and goblin lycanthropes also existed. Most natural lycanthropes viewed their condition as a gift, whereas afflicted lycanthropes were more likely to be horrified by it and attempt a cure, using belladonna or magical means. However, all lycanthropes were usually secretive about their condition because of the social stigma attached to it and many ended up as lonely adventurers.

History
Some said that thousands of years ago, the god Malar used barbaric human tribes to create the original lycanthropes, providing them with qualities of the predatory animals they admired. Others said it was a blessing from Selûne to a group of young human orphans to help them survive in the dangerous wilds. Either way, these ancient bloodlines were passed down through generations. A natural line of elven werewolves known as Lythari dated back to the first elven explorations of Faerun, and the good members of their kind lived among the moon elf and wood elf communities for thousands of years.

Physical characteristics
Superficially, lycanthropes resembled their original species but with the head of the specific animal whose shape they were cursed with. In humanoid form, they appeared no different than before and their natural life expectancy was the same. Lycanthropes could disguise themselves somewhat through their shape-shifting abilities, either taking on a form almost identical to a humanoid but with subtle details revealing their true nature such as pointed teeth or long fingernails. Similarly, lycanthropes could assume an animal form, which would be a perfect disguise except for the unusual spark of intelligence in their eyes that sometimes gave them away.

Groups of Lycanthropes

 * The Akri: a tribe of werecats who lived in the Anauroch desert.
 * The Gray Wolf Tribe: a tribe of Uthgardt barbarians who were all werewolves.

Related Races
Though not technically lycanthropes, shifters were a similar race found where humans had interbred with lycanthropes for generations, acquiring the trait of shapeshifting from their feral ancestors.

Connections
Lykanthropen