Finale of Promise
Oracle Text
You may cast up to one target instant card and/or up to one target sorcery card from your graveyard each with converted mana cost X or less without paying their mana costs. If a card cast this way would be put into your graveyard this turn, exile it instead. If X is 10 or more, copy each of those spells twice. You may choose new targets for the copies.
Cool art, cool concept.
Because this is obviously a candidate for decks cheating things like Restore Balance and Ancestral Vision