Delirium

Instant, 1BR (3)
Cast Delirium only during an opponent's turn.
Tap target creature that player controls. That creature deals damage equal to its power to the player. Prevent all combat damage that would be dealt to and dealt by the creature this turn.¹
Illus. Terese Nielsen

Gatherer Card Rulings [Nov 2009]

• 10/4/2004: Tapping the creature is part of the effect and not the cost, therefore you can cast this targeting a tapped creature.

Format Legality	Legal in Vintage, Legacy Banned in Extended, Standard
Printings (1/6)	Mirage (Uncommon)