Armchair Fighter

Someone who has never fought in their life but has seen combat sports and thinks they're a professional so they write comments critiquing how a fighter should fight. These kinds of basement dwellers are usually found in the YouTube comments of a boxing match, UFC match, kickboxing match, etc.

*Watches boxing match*

John: He needs a more consistent jab, better head movement & keep those hands up. He needs some better footwork as well.

Kyle: Stfu Armchair Fighter