Overmind Realms

The Overminds, or AI controllers of VGO, each reside in their unique realms. While they are able to move where they please, frequently visiting each other as they like, the realms are typically inaccessible to players without the Overmind's permission or a unique questline.

The exceptions of course, being the playable world and the land of the dead (which has one very easy, if not unpleasant, entrance).