Someone who blindly follows the so called metagame, or short: meta of an online multiplayer game. Metafags are the whiny types who complain that you take or use a currently unpopular weapon / strategy or character. The annoying thing about this attitude is, that the meta is being developed by high level professional players, and is thus not as significant for casual players who play the game recreationally and just want to have fun and play the game like they please.
While playing overwatch:

Player1: I will play Soldier.
Player2: No! You musst pick McCree Soldier is not in the current meta!
Player1: Dude, don't be a metafag!
by Kampfzwiebal December 30, 2016
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A trading card player who deliberately pursues in stealing another's deck build from last year's tournament all in all knowing just the basics of how the deck works not fully understanding the game also someone who tends to often play what's hot or a deck that autopilots.
Noob: net decks one of the top five tourney decks brags about being the first to play it claiming originality
Veteran: wow Jim I just slapped another low life trickstar player, what a metafag!
by DickDunkerDuelist December 21, 2020
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