It can be played off of a single Nova, even unupped.
How does this interact with Fractal? Maybe its just me, but I imagine it filling the opponent hand with copies of the target creature, too.
Seems really OP, maybe make it double cost of spells too?
Edit: How does it interact with Nightmare, Adrenaline, Antimatter, Mutation, Freeze, Reverse Time, and Silence?