Guardian of the Golden King
The Fate of Númenor Nightmare#9 (x2)
Enemy
(41) 4 6 4 10
Undead.  
Forced: After attackers are declared during an attack against Guardian of the Golden King, look at the bottom card of the first player's deck. Choose and remove characters from the attack until only X or fewer characters are attacking, where X is the looked-at-card's printed cost (those characters do not ready).