Cannot be optionally engaged. The Balrog and shadow cards dealt to The Balrog are immune to player card effects.
While in the staging area, The Balrog is considered to be engaged with the first player and only the first player can declare attackers against The Balrog.
Cannot have attachments. Allies cannot defend against Orc-chieftain.
Forced: At the beginning of the encounter phase, Orc-chieftain engages the first player.
...he charged into the Company and thrust his spear straight at Frodo. –The Fellowship of the Ring
Cannot have attachments.
For each point of excess damage dealt by Cave-troll (damage that is dealt beyond the remaining hit points of the character damaged by its attack) remove 1 progress from the current quest.
When Revealed: Uruk from Mordor makes an immediate attack against the first player.
Shadow: Attacking enemy gets +1 If this attack destroys a character, attacking enemy makes an additional attack.
When Revealed: Either remove 1 damage from Doom Doom Doom or reveal an additional encounter card.
Shadow: The defending player raises his threat by 1 for each enemy engaged with him.
X is the number of players in the game.
When Revealed: Assign X damage among characters you control.
Cannot have attachments.
Forced: When Slab-bearer is destroyed, discard the top card of the encounter deck. If the discarded card is an enemy, add it to the staging area.
...they bore great slabs of stone, and flung them down to serve as gangways over the fire.
–The Fellowship of the Ring
When Revealed: Discard a randome card from your hand. Assign X damage among characters you control, where X is the cost of the discarded card.