Elemental Plane of Earth
While the Elemental Plane of Fire is blatantly dangerous to outsiders seeking to travel within it, the dangers of the Elemental Plane of Earth are far less so. Obviously, there is no air to speak of but for the occasional elemental pocket, as with most of the planes. However, far more of a danger is the pressure. Often nicknamed the Anvil for exactly this reason, the plane actively works against any attempts at forming empty spaces, whether they be cavern complexes, tunnel systems, or even simple digging; not to say they don't exist, but keeping them from collapsing in on themselves is a constant effort by those maintaining them. Rather than appearing within massive caves as expected by many Primes, visitors to the plane through non-portal means instead appear within crushing stone and dirt itself, often dying within moments if not prepared to protect themselves and becoming one of the innumerous fossils occasionally encountered by others. Nearly all mortal senses are useless within the plane of Earth: sight is pointless through the solid mass that fills the plane, scent is impossible with no air to carry it, and most sound is drowned out by the ever-present grinding of rock against rock. Most natives have no issue, either able to pass through the earth as easily as mortals do air or being sturdy enough to survive the pressure as they dig through it, and with their own strange means of sensing their way through the plane — sensing via vibrations is as common within the Anvil as vision is elsewhere — but to the unwary, even to those that can survive its conditions Earth is nearly unnavigable.
It is such conditions that the elemental vortices leading from the Prime to Earth tend to drop one in, but traveling by portal is a different matter, as nearly all portals tend to connect to those rare occasional regions of empty space that manage to survive either by virtue of luck or by the concerted efforts of the more fragile natives; Dao and mephits especially tend to prefer caves and tunnels to bare stone. Of course, those regions reachable by portal are nothing more but disconnected pockets with no means of travel between them within the plane but to pass through the Earth proper. This is no issue to most travelers and settlers, however, as few have interest in trade within the plane itself. Most outsiders come to Earth for one reason alone: mining. While not as potentially profitable as, say, the plane of Mineral, nor is it as dangerous. While it may lack for gems, the plane of Earth still holds every conceivable stone and ore within its mass, and many seek to make their living extracting these material goods and selling them throughout the wider multiverse.
In either situation, there are yet other dangerous to be watchful for as well within the Anvil. Earthquakes are a common consequence of the infinite masses of stone pushing against one another, pressing until one or the other finally gives and shifts under the force. Minor quakes are a daily event even within the open caverns of Earth, but every so often a major one will strike. If within the mass, such tremors can lead to sudden jumps of pressure that can be dangerous even for elemental beings. Within gaps, major earthquakes can lead to fissures, chasms, or cave-ins, all of which have the potential to be deadly. Within open areas, especially those already bearing an atmosphere through usually-artificial means, gas pockets can also be a severe danger; usually formed from elemental pockets of Smoke or Ooze leaking and spreading through the plane or natural reactions and decomposition of various minerals, gas pockets can, as on the Prime, displace existing air and potentially cause suffocation, though any traveler to Earth ought be prepared for the possibility of having no air at all to begin with. More dangerous, some gas pockets can be explosive, the slightest spark setting them alight and burning through anyone within them, oftentimes leaving an explosion so forceful that entire caverns will collapse to nothing.
There are few surprises when it comes to Earth's effect on spellcasting. As with the other elemental planes, spells of the plane's element are enhanced and spells of other elements are impeded.
- Boundary Regions
- The Inner Planes, pgs.13,30-39,74,80,96,114
- Manual of the Planes (3e), pp.70-74
- Planar Handbook, pp.168-169
- The Planewalker's Handbook, pg.27