Polymorph

Sorcery, 3U (4)
Destroy target creature. It can't be regenerated. Its controller reveals cards from the top of his or her library until he or she reveals a creature card. The player puts that card onto the battlefield, then shuffles all other cards revealed this way into his or her library.¹
"Ahh! Opposable digits!"
Illus. Robert Bliss

Gatherer Card Rulings [Nov 2009]

• 10/4/2004: If there are no creatures in the player's library, then the target creature is still destroyed, you see all the cards in that player's library, and then they shuffle and continue play.
• 8/1/2005: You can play Polymorph targeting an indestructible creature. The indestructible creature stays in play because it can't be destroyed, but its controller still gets to put another creature card into play.

Format Legality	Legal in Vintage, Legacy, Extended, Standard
Printings (4/30)	Magic 2010 (Rare) Core Set - Ninth Edition (Rare) Classic Sixth Edition (Rare) Mirage (Rare)