Plane of Earth
It is a place of hidden riches. It is a wall against all foes. It is a grave for the greedy. Earth is one of the four elements and two energies that make up the known universe and therefore of keen interest to cosmologists. The abundance of large gems and huge ore deposits lured many greedy prospectors to brave the significant dangers of this plane Vortices to the Plane of Earth were nearly always found in the heart of mountain ranges, particularly young ones. Elemental vortices could occur wherever a high concentration or nearly pure form of an element was found, and could be temporary or permanent. The Elemental Plane of Earth was an infinite expanse of solid matter pockmarked by bubbles of other elements and riddled with fissures and tunnels created by burrowing creatures or the occasional small mining operation. Ensconced in a few of these pockets were trading outposts and the rare hidden wizard fortress. Solid does not imply stationary: the substances of this plane were constantly moving in a slow, grinding motion punctuated by earthquakes from small tremors to massively violent upheavals. Open spaces were gradually filled by the relentless shifting (or marauding earth elementals) unless action was taken to prevent it. Air could be found in scattered pockets but unbreathable gasses were also present—unprepared travelers lucky enough to arrive in a cavern might slowly asphyxiate while the unlucky quickly suffocated by being buried alive. Other pockets of magma, water, ooze, dust, or ash were particularly dangerous for miners if they accidentally breached one of these. No light existed in the Plane of Earth except for rare luminous gems buried in the crushing darkness. Gravity in this realm is multiplied by different variables depending on the specific section of it one is in. Every type of rock, soil, mineral, metal ore, sand, and dirt could be found here in abundance, ranging from talc soft to marble tough to diamond hard. Mining operations tended to be small and short-lived because the movement of the substance of the plane and intense gravity caused cave-ins, and the native population defended their territory and/or food supply.