The Lost Lightouse dungeon takes place in a sprawling wilderness area on the sea that's dominated by a huge, monolithic lighthouse structure. Besides the numerous quests that take place in this instance, the group will have to find their way through the foliage and caves to reach the beachhead - cutting through all manner of pirates and grotesque sea-creature themed bosses along the way.
Once on the beach, the group can choose to go two ways. An extra boss can be found by following a deep, narrow canyon that winds in on itself until it terminates in a platform covered in pirates and a boss encounter. Or the group can go straight for the throat and enter the lighthouse itself. Within the lighthouse are multiple bosses and enemies, with the final challenge being located at the very top of the Lighthouse. There's very little room to maneuver inside, so plan carefully.