Specter's Sorrow

Recurve 1-{u} (If you pay this spell's recurve cost while casting it, copy it one time.)
Discard a card. Tap target creature with toughness less than or equal to the discarded card's mana cost. That creature doesn't untap during it's controller's next untap step.
At night, the wailing of the spirits keeps many in the province of Mortius up all night.