Stay Puft

Trample. Protection from combat damage.
As long as your devotion to {w} and {b} is less than 7 Stay Puft isn't a creature.
Anytime your opponent searches their library for any card you may play Stay Puft for {3}{w}{b} as though it had Flash.
When Stay Puft enters the battlefield if you control any Artifact you must sacrifice 1 artifact.