I have always had a love/hate relationship with Planes of Existence in D&D. I loved browsing the original Manual of the Planes – just tons of neat stuff. On the other hand, I never really could figure out what I wanted to do with the concepts. Kinda like going to the proverbial candy store – I look at all the great stuff (outer planes) but walk out just buying a Snickers (ie, the Prime Material Plane). Part of the problem may just be the mathematician in me – the concept of infinite planes of similarly themed “stuff” (demons, fey, etc) just seemed “too much” to really build any coherent adventures. Then you throw in planes like the Abyss which are 666 layers, with each layer supposedly infinite (how odd is that – they are infinite in two dimensions but stack together nicely to be just 666 “vertically”).That said, I have combined concepts from Eberron and Dragonlance to come up with what I think is a workable system that one can actually use both as a player and GM. There are two key concepts:
- The point of intersection of all the planes forms the Prime Material Plane (PMP). At the intersection, each plane lends its primary attribute in the formation of the PMP. The Elemental planes lend their key physical properties to the world (using the old Greek hypothesis of the elements). The “heaven and hell” planes lend their spiritual aspects to the world, etc. This ties very well to Eberron’s planar cosmology – it uses the orbital plane model. In this model when planes are “near” or “far” their effects (or absence of effect) influences the PMP.
- All planes are a distorted mirror of the PMP. On every Plane there is a “city of Sharn” that reflects the main attributes of the plane. On the plane of fire, it is towering volcanoes that are home to a large population of fire creatures. On the Fey plane it is represented by gargantuan trees where a Fey Court rules. On the plane of the dead, it is towers of listless souls—only the souls of the recently deceased goes about their business (see the Eberron’s wiki for a description of the planes). I got this concept from Legends Trilogy from Dragonlance. When Raistlin enters the Abyss to battle Takhisis, the plane appears to be a mirror of the PMP. In this case, it is not, but that is what Raistlin expects and the chaotic nature of the plane provides him that view.
The combination of (1) and (2) provides a more finite concept. The great thing is that the GM now has a map of the plane – it is a very distorted Eberron world map. For the player, they now have some concept of the plane. If they are “trapped” there, the PC can use their knowledge to discover where a manifest zone resides to return them to the PMP. The GM can provide interesting adventures in a familiar yet bizarre setting. One could even have the group go through a previous adventure but with major distortions (extreme example – the pieces of a Rod of Seven Parts are scattered across the PMP and 6 other planes -but all in the same “location” – a GM could run 7 short adventures that are similar in structure but with wildly different challenges).
I do not necessarily have any adventures in mind but I feel this gives me a structure if something unexpected happens (like Mark D having his cleric cast Plane Shift to escape an enemy….)
Update: I did use this concept in my Eyes of the Lich Queen adventure to great affect. After a party wipe, I used it as part of “raising” two of the PCs. It allowed me to add a bit of the temple’s history to the encounter (they got to talk to the spirit of the dragon that guarded the Dragon’s Eye).