Twilight Sparkle, Top Student

Whenever you cast an instant or sorcery, you may pay the converted mana cost divided by two, if you do, search your library for a card with converted mana X or less and put it into your hand, X being the instant's or sorcery's converted mana cost. Shuffle your library afterwards.
"All the ponies in this town are CRAZY!"
- Twilight Sparkle, to Spike