Kuyi, the Aurora Vast

Kuyi, the Aurora Vast costs {1} less to cast for each noncreature spell with converted mana cost 4 or greater in your graveyard.
Flying, hexproof
{2}{u}{r}{w}, Discard a card: Copy target noncreature spell for each spell and ability on the stack. Then exile that spell. When Kuyi leaves the battlefield, return that card to its owner's hand.