Driders (in standard D&D) are Drow men who failed a test their goddess puts everyone who wants to advance from 9th level (I think) to 10th level. They live on the outskirts of Drow cities and eat Drow that come too close.
That was changed in later editions because it makes little sense to look MORE like your god/goddess as a punishment
"DO NOT test my patience. I have little of it for those who would undermine my authority." High Queen Breydice of the Primus Imperium in Empire