Raphael, the Nightwatcher (Showcase, fracture foil) There are plenty of great Raphael cards in the MTG x TMNT set, and the Showcase Fracture Foil variant of Raphael, the Nightwatcher comes in at $280 even
Now obviously, any such list will be subjective from my own vantage point, and with an eye toward kitchen table play, rather than the top tournament contenders
It cant be targeted, damaged, destroyed, exiled, or otherwise interacted with in any way it essentially ceases to exist
The spell that my opponent threw away might never have been able to be played
Pay X mana, sacrifice X zombies, and then reveal cards from the top of your library until you reveal X zombies
Curiously, despite having some great-looking drops with exciting reprints, nothing from the Ultimate Pencil Superdrop has sold out yet