Murphy's Law 8: College? What About It?

[Mutant Sheep]

Thank you! Seriously, you've asked that question like ten times now, so stop! They live in swamps because I want them to live in swamps, and they've got gray skin because they're subspecies of regular elves and the genetic mutations that provide increased resistance to waterborne and mosquito-borne diseases do weird things to drows' melanin!

Somehow I knew there'd be an answer for this question that had SCIENCE. I was just gonna suggest it's "the gods made it that way", because it being a D&D setting obviously means you should go back to the assumptions of the Middle Ages.