Jona, Wild Trickster

Whenever a creature you control is turned face
up, you may pay {1}. If you do, manifest the top
card of your library. (Put it onto the battlefield face
down as a 2/2 creature. Turn it face up any time for
its mana cost if it's a creature card.)
{1}: Turn target creature you control with a morph ability face down.
Morph {1}{u}