I used to mod on various forums. I quit because I was starting to enjoy thrashing the trolls. It's immoral, and I have stopped. Instead I simply quit responding.
But in the old days, I would admonish them not to annoy other members, and then they would usually lay off and come after me, crying "freedom of speech!" I would tell them that the quickest way to get banned was to trouble the admins, who worked tirelessly, for no money, trying to keep things clean and orderly.
That would usually just incite them to flagrancy.
Then I would screw with their account to make them say something totally stupid. They would cry "Nazi!" and I'd tell them "Freedom of the press", and change their permissions. Then after I would make them say all sorts of stupid things and they couldn't edit anything. When they complained it appeared they were arguing with themselves. It was just hilarious.
Eventually they'd make a new account and start over. Then I'd usually ban their IP.
The thing is trolls always follow a pattern. They crap, then say sorry, BUT it really didn't stink unless you have a blahblahblah....
There's never a true apology, but always a fake one. They make it the victim's fault. They turn from logic to insults. They try to create an event.
Nowadays, no event is possible. I just let them blather away like monkeys.