Byleth, Proven Professor

+1: Search your library for a non-legendary creature with converted mana cost 4 or less. Reveal it and put it into your hand. Shuffle your library.
-3: Search your library for a legendary permanent. Reveal it and put it into your hand, then shuffle your library.
-7: You gain an emblem with "You and legendary permanents you control gain Hexproof. Legendary creatures you control gain +1/+1."