Decorated Knight

Morph {4}{u}{u} (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 Decorated Knight is turned face up,
counter target spell. If that spell is countered
this way, exile it instead of putting it into its
owner's graveyard.
You may cast that card without paying its
mana cost for as long as it remains exiled.