Planar Mage

When Planar Mage enters the battlefield exile
target instant or sorcery card from your graveyard.
{1}{u}{u}, {t}: Search your library for an instant or sorcery with the same converted mana cost as a
card exiled with Planar Mage. You may cast that
card without paying its mana cost. Then shuffle
your library.
Ive almost got it!