Test rooms and lings.

[Preid]

Addendum: This could be used with different antagonists as well.
As suggested by wrazzy, ling blood could be of great benefit, but how about wizard blood instead? We all know that the body in this game acts as a container, so how about the wizards spawns with Wizoglobin (totally magical hemoglobin) which could make ~3 powerful chems?
With a werewolf, if you medical scan him, you'll notice he is diseased (this already happens). Bringing him to a test chamber means you could potentially find a cure for his werewolfism through pathology (or you could make him worse)
Vampires can be just sent to the test chambers to be gassed because fuck vampires.

I would love to see a wizard work out a deal with a chemist to sell him his blood in order to have him produce horrible chemicals to be used for golems.