Vortex Cube

The Vortex Cube is a very old and powerful item, a black cube that can be used as a container. If the eight Moonstones of Britannia are stored into it, it has the power to draw and return objects from the Etheral Void. But even without the Moonstones, the Vortex Cube is still powerful enought, to allow teleporting through Britannia.

The Vortex Cube was originally created by Naxalitor for the sole purpose to draw the Codex of Ultimate Wisdom out of the Void. After that, it was stored in the museum. However, the Shadowlords stole it prior to Ultima V, as told later by the Gargoyles, and stored it under Stonegate, using its powers to teleport to every place in Britannia. (meaning that they were unable to do so before) In Ultima VI, the Avatar found the Vortex Cube in the cellars under Stonegate, and used it together with the Moonstones and the Lenses to return the Codex to the Void. After that, the Vortex Cube had lost its purpose, and it was moved to the Museum in Britain, where it could be found in Ultima VII and IX.

Trivia

 * The Vortex Cube was totally screwed up in Ultima IX. It wasn't any longer a cube, and flickered all the time. However, the Vortex Cube in the other Ultimas are black and...a cube.