Noun. Slang term from the game Egyptian Rat Screw, referring to face cards, which allow you to win portions of the hand and are necessary to the strategy of winning. Someone with power cards is in control or lucky. Conversely, someone without power cards is on their way to losing.
Person 1: Hey, congratulations on your team's win!
Person 2: Yeah I know, we definitely had all the power cards last night.

Person 1: Oh wow, you look like a mess, what happened?
Person 2: I broke up with Becky last night. God, I've just got no more power cards.
by Sigma0 December 1, 2005
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