As described by David Sirlin in his e-book "Playing to Win"
A person who plays a competitive game with a personal set of rules that the designers game and the tournament community don't recognize. Usually these rules prevent the scrub from having to put forth the effort to to learn to beat tactics that are above his skill level in a game.
Scrubs will feel that those that don't follow their personal rule-sets as if they were cheating, and complain incessantly attempting to peer-pressure others into following their personal rules for the game.
Scrubs can be recognized by the cry of "That's cheap!" in most player vs. player, competitive video games.
Playing Street Fighter:
Scrub: "You just threw me, that's cheap as hell!"
Competitive player: "Stop being a scrub and learn how to tech throws..."
Playing a Trading Card Game:
Scrub: "Using deck lists off of the internet is unoriginal, and takes no skill since all of the cards are expensive..."
Competitive player: "Whatever, do you want to go best out of 6 now that I've beaten you three times in a row?"
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