The Azure Tree (碧の大樹 Ao no Taiju) is an enormous, magical structure that appears in Zero no Kiseki. Described as the Azure Teasure (碧の至宝), it is KeA's evolution of the Zero Treasure (零の至宝), as being the final phase of Azure Zero Project (碧き零の計画 Aoki Zero no Keikaku)
The interior of the Azure Tree is comprised of different territories, which include The Sanctuary, the cavernous Territory of Shou, the garden-like Territory of Siki, the hellish Territory of Gou and the chained labyrinth Territory of Kai. The final chamber, The Farthest, is where KeA is held captive and where the Azure Demiurge is fought.
Territory of Shou
A cavernous area with lightning strikes. It is here where Demon Wald is fought.
Territory of Siki
Territory of Gou
Territory of Kai
The chained labyrinth of Kai.
The Road of Farthest
A short area with a path leading to the The Farthest, the final area of the tree.
The final area where Mariabell is encountered along with the imprisoned KeA. The Azure Demiurge, using KeA as its core, is fought and defeated here.