Mirage
Delirium


Instant 

(CMC:3)
Play only on target opponent's turn. Tap target creature that player controls. That creature deals to the player an amount of damage equal to its power. The creature neither deals nor receives combat damage this turn.
MI • ENTerese Nielsen
™ & © 1993—1996 Wizards of the Coast
Legal in: Mirage Block,Legacy,Vintage,Freeform,Prismatic,Tribal Wars Legacy,Singleton 100,Commander
Oracle Text (click to copy):
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10/4/2004 Tapping the creature is part of the effect and not the cost, therefore you can cast this targeting a tapped creature.
Card Delirium is not on TCGPlayer.