Cursed Lands

Yes, there is a curse spell there. I can't remember exactly where I used it, but I remember using it to finish off the last monster, casting the curse with a mage... That creature died much faster.

Yes, there is a curse spell; maybe it's just called something else. At the beginning of the game, you get an amulet (or something similar) with a curse spell as a reward for completing a mission. If you cast it on, for example, a boar, its damage and health will decrease by a percentage (and the boar will also shrink in size).