Khefnet's Denial

Counter target noncreature spell if it's converted
mana cost is equal or less than the number of Survivors you control. If you control 5 or more Survivors, return Khefnet's Denial into your
hand instead of your graveyard as it resolves.
"Your order for me was to protect the citizens of this
city. I will follow your orders to my grave."
—Khefnet, Avatar of Knowledge to Nicol Bolas