Muddle the Mixture
{U}{U}
Instant
Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard ~this~: Search your library for a card with the same mana value as ~this~, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)
Quash
{2}{U}{U}
Instant
Counter target instant or sorcery spell. Search its controller's graveyard, hand, and library for all cards with the same name as that spell and exile them. Then that player shuffles.
Stratus Dancer
{1}{U}
Creature -- Djinn Monk
2/1
Flying
Megamorph {1}{U} (You may cast ~this~ face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When ~this~ is turned face up, counter target instant or sorcery spell.