Final Fantasy XI: Seekers of Adoulin is the fifth full expansion pack for Final Fantasy XI, and the first full expansion for Final Fantasy XI in over 5 years after Wings of the Goddess. Seekers of Adoulin is set in the western continent of Ulbuka and features new jobs, story, areas, quests and gameplay systems. PlayStation 2 support for Seekers of Adoulin is only available in Japan. Although Square Enix is not dropping PlayStation 2 support for Final Fantasy XI as a whole, Seekers of Adoulin content will not be accessible on Final Fantasy XI for PlayStation 2 outside of Japan.

Ulbuka — a land of unexplored wilderness — welcomes any who dare discover its hidden secrets. Unexplored lands, undiscovered treasures, and untold dangers await those brave enough to set foot into the wilds, whether with the swords and sorcery of old, the bells of the primal Geomancers, or the arcane arts of the stalwart Rune Fencers.