The Chronicling of Aeolor
Aeolor is part of a multidimensional Cosmology. during your adventures it is possible that you may journey into familiar worlds or planes.
Planes are the same as the normal rules set except for the following
Abyss/Nine Hells: These planes are no longer separate. Instead, both Demons and Devils inhabit the abyss, which is no longer a realm of infinite layers. But a single layer that extends infinitely in every direction. The abyss is divided down the center, Demons inhabiting one end, Devils inhabiting the other. In the middle of the plane, the blood war rages, a never-ending battlefront that divides the realm in half, Demons and Devils both attempting to destroy each other.