World of Warcraft Quests involving Darnassus Sentinel:
Western Plaguelands Alliance Quest
All Along the Watchtowers Using the Beacon Torch, mark each tower in Andorhal; you will need to stand in the doorway of the tower to successfully mark it.
Once all four towers are marked, return the Beacon Torch to Commander Ashlam Valorfist in Chillwind Camp, Western Plaguelands.
Fallen Sky Lords (Alliance) Travel to Frostwolf territory and search for Wing Commander Slidore, Wing Commander Vipore, and Wing Commander Ichman. Return to Commander Duffy should you complete your mission.