As anyone who's put up with these assholes for even a moment knows, mooks & trolls need air to survive just like the rest of us.
The best thing to do is: Never respond to them and their childish baiting & lies.
If they defame you, if they smear you, find out, document, and wait for later. If they've gone over the legal limits of our proscribed rights in society, the onus will be on them. The best thing to do is to never respond.
Hard, I know, and we all slip at some point. There are times to set the record straight too. But the fact is, these assholes exist in a fringe echo-chamber. Normal people don't listen to or buy into their lies. That's all you need to know in the end. Let them do all the talking, the defamatory scribbling--let them dig their own graves. It's about all they're good at.
Let the fuckers suffocate.