Alternate planar arrangement
by David KnottHere is a scheme that would enable us to make use of most of the existing Planescape material without accepting the good/evil alignment axis added in AD&D or any of several other items that are incompatible with the Mystara setting:
Inner Planes: These can be lifted from AD&D sources intact with one single exception -- no Immortals/Powers claim the Prime Material, Ethereal, or any Elemental plane as home. Suggestions for relocating such Immortals will be given later. Also, the Inner and Outer Planes have more inter-connections than in the standard cosmology, as explained later.
Prime Material Plane: This can also be lifted from AD&D sources intact, right down to the crystal spheres and phlogiston. However, the crystal sphere corresponding to "Mystaraspace" has one rather nasty characteristic: it exists and is accessible only from the outside. One a spelljamming ship enters that sphere, it cannot return the way it came -- its only options are to wander out into the vacuum between the stars (to almost certain doom, as magic works only within the Mystara solar system) or to land on a planet and then use planar travel to get back home.
Furthermore, the exact "twist" one takes when entering the Prime Material Plane in general and Mystaraspace in particular govern which dimensional aspect of it one reaches. Most travellers reach the "Normal" dimension and never find out about the alternatives. The opposite from normal approach lands one in the "Nightmare" dimension, home of the diaboli. A truly perverse method of entry (possible only for somebody of Immortal or better intellect) will land one in the "Vortex" dimension.
Astral Plane: The Astral Plane is the realm of mental constructs and thus its form is based on the expectations and beliefs of those who travel in it. The only Outer Planes that an astral traveller can reach voluntarily are those that the traveller believes in. Travellers from Mystara have the advantage of believing in the connection between the Astral and Ethereal planes and thus do not need to observe the restrictions on invoking ethereal or elemental spell effects on the astral plane or vice versa. However, their lack of belief in the connection between the Prime and Astral planes prevents astral projection spells and effects from working for them. Of course, with proper experience and education any Mystaran or non-Mystaran planar traveller can learn to overcome either of these limitations.
Outer Planes: Since the Law/Chaos alignment axis is intact, those planes that correspond to the "pure" alignments of Law (Mechanus), Neutrality (Outlands), and Chaos (Limbo) also remain intact. The "Lower Planes" are associated with Entropy or Destruction in some form, while the "Upper Planes" are associated with Creation (the other four Spheres). The main Powers associated with these planes would be Primus (Mechanus), Azathoth (Limbo), and Ao (?) (Outlands).
Lower Planes: The change of these planes from "Evil" to "Entropic" should leave these planes mostly intact, with one exception: "Evil" Powers who correspond to non-Entropic Immortals are evicted from these planes and relocated to the Upper Planes. The principal Lower Planes known to Mystarans are Pyts (aka the Abyss -- the home plane of most Immortals of Entropy), Baator (the source of the lawful fiends who trouble the Nightmare Dimension), and the Grey Waste (the main battleground of the Blood War).
Upper Planes: Replacement of the "good" alignments with the four creative Spheres completely changes the available upper planes. From Law (Mechanus) to Chaos (Limbo), the new planes are as follows:
Brynn (Matter)
Beastlands (Matter/Time conflict --> life)
Entrem (Time)
Elysium (Time/Thought conflict --> dreams)
Mirage (Thought)
Radiance (Thought/Energy conflict --> arcane power)
Draesten (Energy)
Obviously the inhabitants of the "good" planes would have to be radically rearranged under this scheme, but from the above descriptions (along with the Sphere assignments in WotI), it should not be too difficult to work out that rearrangement. Mortal inhabitants can generally be left in place unless they live in unusual environments -- for example, aquatic inhabitants of the Upper Planes would tend to be concentrated in the Plane of Entrem, or perhaps in the "Archomental Plane of Water" that is connected with it.
Archomental Planes: These planes are the philosophical counterparts of the physical elemental planes. They are connected not only to the corresponding elemental planes but to the corresponding "Upper" planes. Elementals may be summoned from these planes as well as from the standard Elemental planes -- but the elemental dominance rules, based as they are on the relationships among the Immortal Spheres, affect only those beings summoned from the Archomental planes. Powers who supposedly claim Elemental Planes as their home planes actually dwell in the corresponding Archomental planes.
Draconic Planes: The home planes of
lawful, neutral, and chaotic dragons, respectively, would be
connected to the Beastlands, Elysium, and Radiance, respectively.
The home plane of the Great One would be hidden among the home
planes of the other draconic Immortals.