Ninja Frogs

Whenever you cast a creature spell, if Ninja Frogs is in your hand you may cast the creature with Ninja Frogs under it, if anyone catches you doing this, destroy Ninja Frogs. Whenever the creature that Ninja Frogs is under blocks, you may take Ninja Frogs out from under that creature, if you do, Ninja frogs becomes the creature blocking.
Ninj-ibbit!