Exhaustion
Sorcery
Creatures and lands target opponent controls don't untap during their next untap step.
Starving and worn, Cao Cao escaped from the battle of Red Cliffs with only 27 of his original 800,000 men.
Qu Xin
Rulings
No creatures or lands controlled by the player will untap during their next untap step. This includes those which entered the battlefield after Exhaustion resolved.
(wotc • 2009-10-01)
The creatures and lands are only prevented from untapping during the targeted player’s next untap step. They can still can untap during other player’s untap steps.
(wotc • 2004-10-04)
Rulings
No creatures or lands controlled by the player will untap during their next untap step. This includes those which entered the battlefield after Exhaustion resolved.
(wotc • 2009-10-01)
The creatures and lands are only prevented from untapping during the targeted player’s next untap step. They can still can untap during other player’s untap steps.
(wotc • 2004-10-04)