Actually, my first experience with Revenants... well, they got a taste of their own medicine before I even knew what they were REALLY capable of, in MAP06 of Doom II: The Crusher. It was in a later map that I really began to HATE them.
The Revenant is a skeleton-type enemy from the hit game Doom, the only stock monster capable of firing these annoying-ass and extremely powerful heat-seeking missiles. Though they have relatively weak hit points compared to other monsters, such as the Hell Knight, they can be a dangerous nuisance if left alone.

Jake Pryde (C)  prdarkfox
Doom (C) id Software