The Fourth-Dimensional Space is the universe where the Fourth-Dimensional Beings reside. While this Universe resides in four dimensions, third-dimensional beings can enter this realm provided they have the Alteration gene.
The universe where the 4D beings, who are thought to have created the universe of Fayt and friends, live. No information is available on this universe. According to the research of Dr. Leingod and his team of scientists, the relic on the planet Styx known as the Time Gate is actually an entrance to this 4D space.