Throngs of Unfaithful
The Grey Havens#70 (x2/x1)
Enemy
(26) 1 2 0 4
Undead.  

Surge.

Forced: When Throngs of Unfaithful is defeated, discard the bottom card of the engaged player's deck. If that card’s printed cost is 2 or less, return Throngs of Unfaithful to the top of the encounter deck.