A 'lone
enemy' is an enemy
unit that's not entering simultaneously with another enemy unit. Stationary units at the
Troll Bridge ignored.
Here are some examples: If an enemy
War Horse is carrying its
Avatar and moves to your Troll Bridge, it will not trigger, since
there are two enemies entering simultaneously. If your
Bodach Bogeyman is carrying two enemy minions and moves to your Troll Bridge, it will not trigger. However, if the Bogeyman were carrying just one enemy, the Bridge would trigger. If there is already an enemy occupying the Troll Bridge and another enemy unit enters, it will trigger for the entering enemy.