The key is to come up with something that people are always willing to argue both sides of and then pick the side that people will be most reactionary against. The goal is to get a bunch of people arguing against each other with as minimal input on your end is possible. Then you get to sit back and enjoy the show.

Lol I'll just use gays

That topic usually works pretty well lol.

Lol

Try telling them that God doesn't exist. That works really well. Did that in WoW before , logged out, came back an hour later and they were still going.