Aven Liberator

Flying
Morph {3}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When this creature is turned face up, target creature you control gains protection from the color of your choice until end of turn.

The List

Scourge

Flying
Morph {3}{W} (You may play this face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Aven Liberator is turned face up, target creature you control gains protection from the color of your choice until end of turn.

Morph

(You can cover a face-down creature with this reminder card.
A card with morph can be turned face up any time for its morph cost.)