Trollhunter

A trollhunter or trollbuster is a user of an internet forum who, while not actively inciting conflict (as a troll) would, eagerly escalates conflicts as soon as they are incited. Frequently, they "pounce" upon trolls with aggressive flame messages, and are often as detrimental to the discussion as the original instigator.

Trollhunters are sometimes called "second strike trolls", as they use other trolls as an excuse for their own aggressive posting. Quite frequently, they also falsely accuse confused or controversial posters as trolls.