Wrax, Madcap Machinist

Flying
{x}{u}{r}, {t}, Sacrifice Wrax: The next instant or sorcery spell with converted mana cost X you
cast this turn gains storm. (If a spell has multiple
instances of storm, each triggers separately)
"Goblins in the Izzet League range from expendable
labrats to burnable fuel. Wrax just chose to burn on
his own terms." -Ral Zarek