MAGIC: THE GATHERING
Search your library for a green creature card with converted mana cost X or less, put it onto the battlefield, then shuffle your library. Shuffle Green Sun's Zenith into its owner's library.
Tutoring a green creature directly onto the battlefield is powerful. Green Sun Zenith has been universally adopted in decks with lots of green creatures. It can ramp on turn one by fetching Dryad Arbor and provides a huge toolbox of interactive creatures.