Astroblast

Astroblast enters the battlefield with one artifact counter.
{t}, Remove one artifact counter from Astroblast:
Search your library for one artifact. Astroblast
doesn't untap during the controller's next untap
step.
{x}{2}: Send target creature card back to it's controller's hand, and pay X, where X is the converted mana cost of the creature.
Doesn't take much to send you flying.