He has one interesting power (ability to use t'a'r, which is rapidly becoming something even novices will be able to do on a regular basis once they get enough ter'angreal) and he totally does not use it except to kill rabies-infected wolves that get high on LSD and communicate telepathically with each other. I mean the fact that Hopper is still alive and never mentions to Perrin about being hunter by Slayer in t'a'r (well, maybe he mentions this once, I don't remember for sure) tells us that Slayer is a terrible waste of a villain.