Fallen Into Evil
The Fellowship of the Ring #159 (x1/x0)
Treachery

When Revealed: Attach to a non- hero and move it to the first player's staging area. (Counts as a Condition attachment with the text: "Attached hero loses the hero card type and gains the enemy card type with Threat equal to its Willpower and engagement cost equal to its threat cost. If Fallen into Evil is discarded, return attached hero to its owner's control")