Elemental Planes

The Elemental Planes are situated deep within The Chaos and exist as infinitely realms dominated by the elemental force that is attached to it.  Gateways and portals to the elemental planes can be opened on the physical plane, and in fact, many magic users have made use of this to pull forth elementals to bind to servitude.
Each Elemental Plane is ruled by two greater elementals, known as the Archomentals.  They each represent the positive and negative aspects of their respective elements, like how Fire is both a bringer of life and warmth but also destruction and ruin.  The Archomentals, while considered both Primordials and Gods of Chaos, still answer to The Elder Elemental.
There are six Elemental Planes in total, representing the forces of Air, Water, Fire, Earth, Energy and Entropy.