The Tuatha De Danann (トゥアハ・デ・ダナーン), also known as the Empyreal Fortress (幻想機動要塞), is a flying fortress used by the Kin of Earth during their war against the Kin of Fire prior to the Great Collapse. It is said to be their ultimate creation.
When it appeared above Osgiliath Basin on 30 August, S.1206, it was accompanied by five pillars similar to the Salt Pales. It is speculated that the residues remaining in the earth were used to fortify the construction.
The party consisting of Class VII (Old and New) faced several roadblocks throughout their incursion into the fortress. They included, in order:
- Lechter Arundel and Claire Rieveldt
- Cedric Reise Arnor and Shirley Orlando, with the Fourth Rivalry taking place with Cedric piloting Testa-Rossa
- Mariabell Crois and Campanella
- Black Alberich and Rufus Albarea, with the Fifth Rivalry taking place with Rufus piloting El-Prado
- McBurn in his true, otherworldly demonic overlord form
- Giliath Osborne, with the Final Rivalry taking place with Osborne piloting Ishmelga
Afterwards, Class VII teamed up with all five of the teams dispatched to the Salt Pales to defeat Ishmelga in its true form and brought the curse of Erebonia to an end.
- Tuatha Dé Danann are a supernatural race in Irish mythology. Family members of the Tuatha Dé Danann include Lug, reminiscent of the geologist persona's name Black Alberich assumed in Trails of Cold Steel III, and Balor, referring to Black Alberich's combat shell, Zoa Balor.
- Trails of Cold Steel IV, Act 3: "Seekers of the Dawn", 08/30. Cite error: Invalid
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