those would be cool

. lemme think of another fun one:
Penalty Game
Type: quick-play spell
Effect: When your opponent activates a card that would end the duel in one turn, inflict 7999 points of damage to your opponents life points before the effect of your opponents card is activated.
Picture: Yami Yugi pointing at the screen yelling "penalty game"

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Shadow Game
Type: Spell Card
Effect: This card can only be activated during main phase 2. You can not play any cards or activate the effects of cards you control for the rest of your turn. Decrease your life points by 1/4ths. The winner of this duel wins the match.
Picture: Marik laughing in the shadow realm

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