So they were a sadist, in one case I always thought it went much deeper mentally.
I won't mention their handle else this reply would be a trophy.
One user on the Usenet was fairly bright, and was able to hide themselves this while running a website that was never popular but had some very good in depth Windows help. Nobody ever did locate them other than the country they lived, they were that good.
They did indeed have a problem, being so offensive to everybody all the time just isn't normal. Your aware with Usenet you can't just ban somebody, they are there when they wanted, for as long as they wanted, as close to their heaven as this person could get.
The newsgroup I frequented was their home base, I just ignored them no matter what was said and all was good on my end; it's the ones that replied that took the brunt of verbal abuse (ah duh), nothing was taboo here. I never did block them, I guess I had a morbid curiosity over the situation.
Coming into to a newsgroup for the first time and being viciously verbally attacked for no reason - people respond to put themselves in a better light or above this person; it never ended well for them.
I've seen them make people so mad they swore their lives purpose from that moment on was to find this person and rip portions of their body off (always something painful and slow). They on the other hand I'd never seen threaten or suggest harm to anybody, just verbally abuse.
This was a bright mentally ill person, (many diagnosis were made) who drew no greater pleasure than making people mad, upset or a real prize was someone who tried to keep up with them, they were the ones in the end willing to swim oceans to find them.
I've never seen anybody else coming close to this persons trolling, they never lost, always coming out on top of their game; and I watched it go on for some 6 years, and they were very much part of the newsgroup when I first subscribed to it.
Funny thing I just checked expecting to see them still at it, they quit posting the same month, year I quit posting - I found games and haven't been back. Mayhaps someone caught up with them. Yet their post are normal right up to the end.
No I didn't read any of the articles, I've seen one of the best in action; there is something mentally wrong with them, reading the meaning for sadist they do/did fit the description very well.