Name: Whir of Invention
Mana Cost: {X}{U}{U}{U}
Type: Instant
Oracle 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.
Collector Number: 49
Set Code: AER
Set Name: Aether Revolt
Rarity: Rare
Finish: Foil