The Dimension Castle is an arena in Dissidia Final Fantasy. It is the representative arena of Final Fantasy V. A big arena, it consists of several big castle-like platforms. Other than that, the arena is pretty simple, the only special feature is the vast space for wall running.
However, in the Dynamic version, Castle parts warp into different configurations after set intervals. During the transitioning phase, 50 BP is added to the Brave Pool each second.
The dynamic version can be bought at the store under the system section after beating Shade Impulse.