Drider

Driders are drow (dark elf) aberrations that have been transformed from the waist down so they have the body of a spider. The transformation is typically a punishment for offending their goddess, or failing a test of Lolth.

Ecology
Only high-level priestesses in good standing with Lolth are able to initiate the transformation of a dark elf into a drider. This transformation is very painful, and lasts at least 12 hours. Driders develop a poisonous bite. Their digestion changes and they must drink blood of living creatures for sustenance.

Driders still maintain the spells and special abilities they had developed as a drow, thus there can exist any character class of drider. They retain intelligence and memories. This usually makes them bitter, spiteful creatures. Some hunt for magic powerful enough to undo the transformation.

Environment
Driders are most commonly found in the Underdark.

Typical physical characteristics
Driders are centaur-like creatures, appearing as drow from the waist up, with their lower portions replaced by the abdomen and legs of immense spiders.

In previous editions, driders appear sexless due to bloating, but able to magically reproduce. Currently, in 3.5 Edition D&D, driders seem to retain their gender and characteristics after the transformation, but fertility is debatable.

Alignment
Driders are always chaotic evil.

Society
Driders play many roles in drow society. The dark elves both fear and are revolted by driders. After transformation, they are usually pushed to the wild area around a drow city. Driders are usually found in company with tiny, huge and giant spiders.

Driders speak Common, Elvish, and Undercommon. In the first and second editions of the game, Driders spoke Drow.