Oracle

Enchantment 

3U: Target opponent reveals a card at random from their hand. If it's an instant or sorcery card, exile it. You may cast it without paying its mana cost for as long as it remains exiled. (If it has X in its mana cost, X is 0.) At the beginning of the next end step, if you haven't cast it, return it to its owner's hand. Activate this ability only any time you could cast a sorcery.

Tournooi-info

Legal in: Vintage, Legacy, Commander

Officiele rulings

10/4/2004
If the opponent has no cards in hand, then the ability does nothing.

10/4/2004
If Planeswalker’s Mischief leaves the battlefield, any cards it exiled are still under the effect of the ability and can be cast (and if they are not cast, they are returned to the owner’s hand).

10/4/2004
When cast, the card goes to its owner’s graveyard after it resolves.

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