flavorText: "Magic hat, I'm gonna be frank. What we need now is a twenty-ton tank!"
name: Whir of Invention
printings: AER, KLR, PAER, PLST, SLD, SPG
text: Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
  Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.
type: Instant