- You may be looking for Atlantis.
Zordin, later Atlantis, was a world created by the Great Leader, and later maintained by the Epoch. It was the capital planet of a number of worlds whose history before Year Zero was erased. In truth, it was an altered form of Earth in some timeframe. (AUDIO: Year Zero, Dead Man's Switch) It was described by Bernice Summerfield as being "a few millenia back and slightly to the left" with respect to her time, the 27th century. (AUDIO: In Living Memory)
The Great Leader, and later the Epoch, kept changing the world, including names of people and places (including the name of the planet). When Bernice Summerfield arrived there, it was similar to the mythical Atlantis, although from the orbit she recognised it as Earth. (AUDIO: Dead Man's Switch)