If you have Anuril attached to a hero and exhaust Anduril to trigger the ability must the hero attack the enemy alone or resolve the attack with the aid of another non-exhausted character able to join in for a combined attack?The hero attacks alone. However, you can declare a separate attack against that enemy as usual once all enemies have attacked.
If The Great Bridge (Journey in the Dark) is explored and the Balrog is not yet in play am I correct you cannot trigger the effect of this card and damage the Balrog? I just ran this quest again and actually traveled through before the Balrog was able to enter the staging area. You cannot damage the Balrog while it is not in play, so you'll either want to wait until it is in play to travel to the bridge, or else travel there when you think you will be able to finish the quest before the Balrog enters play.