Cypher ~ The Unbound
There are many different dimensions in the multiverse, here are but a few that are known:
Without a better name for this strange world, that appears to be where all other worlds connect to, it has been dubbed the Nexus.
It is a flat world. It spins around a central axis. It has a sun, but no moon. Atmospheric interference prevents one from seeing too far in any one direction.
It has a significant landmass, the continent of Hemas. It is unknown as yet if there are other significant landmasses. There are islands, however, like the Geliek Archipelago.
The world of Dr. Edgar Islington. It's Earth, but different. Because of all the bird people.
The world Sevetar hails from. Lots of dense forests and lakes and big old stone manors.
The world of Honsu. There's like a desert or something.
The world Tyrus Pern originates from. The singular city, Luthadel, is the capital of the Final Empire.
The world Mildred comes from. Filled with rustic farmsteads advanced cities, a whole bunch of useless things that people buy for some reason, and chocobos probably.
Think fantasy land, but where all mages are dicks. Although Idrius comes from Cularus, somehow its inhabitants never got around to inventing gears or cogwheels. Most likely because they were too busy being dicks.