The Castle Oblivion, a twisted maze of nothing, and home to the Organization XIII and their Nobody servants. The Castle of Nothing, The Ruins of Order, The Citadel of Non-Existence are among some of the nick names that it has been given, but it's roots lay in the history of it once being home to the Keyblade Order, before the Nobodies took over during the Keyblade War and claimed it as their own, warping the world from The Land of Departure into the wasteland of open fields and winding roads that surround this castle.
Organization XIII

I - Xumyi
II - Culsax
III - Xadrren
IV - Xima
V - Laxed
VI - Xavier
VII - Exmaji
VIII - Rixahs
IX - Daxline
X - Maxchiel
XI - Hendrix
XII - Jaxson
XIII - Raixa

Note: If no player is listed beside the name, it's a NPC.