Inner Plane

The Inner Planes are the core of the multiverse. Each elemental plane contains the pure ingredients that form the building blocks of the universe. Earth, Air, Fire and Water are the four prime elements which, when combined with each other, form the 4 para-elemental planes of Ice, Magma, Ooze, & Smoke. Combined further with the 2 energy planes (Negative & Positive, or Void & Light), we get another 8 quasi-elemental Planes. These are Lightning, Radiance, Mineral, Steam, Vacuum, Ash, Dust, and Salt.

Earth + Fire = Magma
Earth + Water = Ooze
Fire + Air = Smoke
Air + Water = Ice
Positive + Air = Lightning
Positive + Fire = Radiance
Positive + Water = Steam
Positive + Earth = Mineral

Negative + Air = Vacuum
Negative + Fire = Ash
Negative + Water = Salt
Negative + Earth = Dust

Exploring the elemental planes is dangerous. With the exception of Air, each of the planes has formidable natural conditions that are often inimical to mortal life. Fire is fatally hot, Earth will suffocate you, and Water will drown you, not to speak of the life-leeching capability of the plane of Ash & others. Canny planewalkers will always bring magical protection from the elements, and would do well to hire a local elemental guide in each plane. Be peery of the genies, for they are always tricky and often malevolent.