It's clear he's got a weapons obsession. A large percentage of his posts revolve around that. Why anyone would be cheerful about such things makes zero sense to me, but it seems he gets off on killing.
Yes, he's got quite the reputation for forcing longtime users off of Hive. Seems he's the self-appointed rabid Hive police dog. He's also got a reputation for being inappropriate with some users.
pathology which takes great pride and satisfaction in hurting other people
I agree. Interestingly enough, when you google you've said above it brings up links about psychopathy.
You've hit the mark in all that you've said.