(Rule Shark, Ruleshark)

Yu-Gi-Oh slang for a player (often of high ranking) who is constantly and obsessively bitching over rulings. When ever a rule shark comes across anyone who breaks the rules is even the slightest way, even mistakenly , they will do everything in their power to get the person penalized. Rule sharks are most often found on the now popular Dueling Network website where they prey on unsuspecting victims in rated matches in order to gain rank. Most rule sharks go un-penalized due to the fact that they are technically not breaking the rules, however if one is proven guilty of rule sharking it is treated the same as boosting ; a form of cheating. Rule sharks are the reason most players avoid competitive matches
Example of a Ruleshark:
Player 1 mistakenly uses a card and takes his move back.

Rule shark: Hey you cheater you cant do that

Player 1: Sory, I messed give me a sec

Rule Shark : Why? so you can cheat more

*Rule Shark calls admin*

Player 1: Dude, what the hell.

Admin: Ok, whats up?

Rule shark: He's Cheating and he cursed

Player 1: But I....

*player 1 has been baned*
by Nyan Dragon January 25, 2013
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In the Yu-Gi-Oh Trading Card Game, a rule shark is a fucking douchebag who knowingly tries to confuse their opponents into mistakes by questioming obvious card interactions and bitching about completely legal interactions and mechanics to try and swing the game in their favour. Basically a cunt who saps whatever life and fun is left at an event.
Example
Player: During your Draw Phase, after you've drawn your card, I activate my monsters Quick Effect.
Shark: Too late, the draw phase has already passed as soon as i've drawn my carf.
Player: thats BS and you know it you fucking faggot. Stop being such a Rule Shark.
by Dark Night Enforcer July 13, 2016
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