Magewright's Stone
Dissension — uncommon
Artifact
Magewright's Stone rulings:
2006-05-01: If an activated ability with in its cost is granted to a creature by an effect (such as Hypervolt Grasp’s effect, for instance), Magewright’s Stone can untap that creature.
2006-05-01: This looks for the symbol. The phrase “tap an untapped creature you control” isn’t the same and doesn’t count.