Flaming Sword
Journey in the Dark Nightmare #7 (x1)
Treachery

When Revealed: Attach Fiery Whip to The Balrog (even if out of play) as a Weapon attachment with the text: "Attached enemy gets +1 Attack and gains Regenerate 4. (At the end of the refresh phase, remove 4 damage from the attached enemy.)"

Shadow: If attacking enemy is The Balrog attach Flaming Sword to it.