Creature — Human Wizard 1/1, U (1)
Common
At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.
Illus. Nils Hamm

9/22/2011: You may reveal the card even if it's not an instant or sorcery. Whether or not you reveal it, the card stays on top of your library.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Extended (Type 1.X)
Legal in Standard (Type 2)
Legal in Classic (MTGO)
Legal in Commander
Legal in Modern