During the Cataclysm, some of the other planes experienced a level of distortion. The Elemental Planes took it especially hard; the dimensions were pushed from their places and set astray in the Astral Plane, becoming planets in nature. Now these planes exists as globes, celestial bodies that can be reached in outer space. They are acutely attuned to their respective elements, and hence take on ecosystems that reflect them. The creatures here are fierce, but usually the inhospitable climates make the Elemental Planes survivable for the average adventurer.
There are two main ways to reach the Elemental Planes. The first is to sail there from the Astral Plane, which requires specific equipment to execute. Once you make it into one of their orbits, you must successfully land the ship and leave it, bracing the outside environment. Landing in certain planes could cause damage to your ship. The other way is to find a portal to them. There are small ones that pop up around Morgath from time to time, but these are rarely easily accessible. However, the largest portals are slowly being unveiled, accompanied by vast structures known as the Labyrinths of the Planes. These can only be accessed by certain players for certain reasons, so talk with the GMs (particularly NecrotiX about the labyrinths) before doing much with these portals.
Pushed freely into the Astral Plane, the Elemental Planes suffered drastic deformations. Gravity took over, bending the planes into globes and giving them orbits. On their surface, the climate has adjusted, allowing odd formations and entire ecosystems to spring up. The four main planes: Unseve, Muspeil, Grumen, and Ysil, all orbit in rings around the heavens. Each has its own properties to be accounted for astronomically.
Each planet has moons. The four major moons are formed from paraplanes and include Wynt, Ezer, Linj, and Urg. When two major planes come near each other, these moons are able to leave one plane's orbit to join another's, and thus draw influence from multiple planes. Due to the timing of the orbits, these planes only ever are around one of two of their possible moons.
The minor moons, formed from quasi-planes, do not change orbit. During the cataclysm, the planes of Negative and Positive energies were overloaded and imploded on themselves, amplifying their influence and allowing the minor moons to maintain their own energies. As such, the minor moons are the legacy of different energies, and have their own takes on their base environments. Remnants of the Plane of Positive Energy include the moons Infiyt, Azzelyf, Orgonutt, and Thesyn. Meanwhile, the Negative Energy Plane birthed the moons Niff, Sihn, Oukinlomu, and Thaum-Rygr.
Unseve, the Domain of Water, houses the highest concentration of elemental known in the entire multiverse. A celestial sphere composed almost entirely of water, it is thought to be a truly infinite ocean. This plane is sometimes thought the goal of ambitious sailors, who wish to brave the strongest sea.
Unseve is composed of three main regions. When you land first within the planet's atmosphere, you find yourself among endless waters. Land is rare and usually presents itself as floating sand banks, suspended in the water. Often ships require aquatic landing gear to remain buoyant on the waters surface; otherwise landing requires a clear stretch of sand with a high enough shore that the island wont sink beneath the ship's weight.
The biggest and likely most impressive region is the underwater. No matter where you are under the sea's surface, it constantly appears as if you are not far below the surface. Light here seems rather unaffected by the water, which is extremely clear. Long columns of dark sedimentary stones rise through the water, boasting ecosystems of kelp and schools of various fish and creatures among them.
The last region is the hardest to reach, and it is the lower caves. Under the water, there are many caves in the rocks; some are engulfed in water, others offer brief respite from the lack of breathable air outside. Light does not reach them, making the waters akin to a murky black abyss. Survival for any organism in this region is difficult and requires extreme care and attention to details.
Unseve harbors a thriving ecosystem of fish, coral, barnacle, and elementals. The surface sands are often full of crabs and crustaceans seeking refuge near the little breathable air. Occasionally, tropical grasses and trees sprout up; this is thought by locals to had been brought originally by visitors from the Astral Plane and eventually implemented into the ecosystem.
Beneath the surface, the various species of fish, corals, aquatic flora, and primal elementals form their own food chains and biotic relationships. Often times aquatic flora require the surging currents of minor water elementals to clean them of sand and salt to keep them thriving. Fish tend to stay away from the elementals for fear of being swallowed up, but require the plants for sustenance. Life under the sea comes in a variety of colors and shapes, making it a vibrant scene.
Deep within the caves, where light does not shine, the life has adapted to a more dreary environment. Many fish sport sickly green bulbs to shine light for wayfinding. Large plants might use reflective fibers to catch the eye of such fish and attract them over to them. Most fish in the area are carnivores, as the plants do not produce enough energy during photosynthesis to support themselves, let alone a larger and more complex organism.
There is no place hotter than Muspeil, the Domain of Fire. During the Cataclysm, the plane of elemental flame was condensed, superheating the atmosphere and turning it into a gas giant. Now, the hardly breathable atmosphere of oxygen, carbon, nitrogen, and sulfur floats in various, dense layers.
To say Muspeil has a surface would be hardly true. The majority of the planet is composed of hot gases, which float in different layers of concentration around a plasma core. However, over time various metals had reacted with the carbon in air, forming flat landmasses which float on the dense gas. Colored deep reds and blacks, it is formed of metal ores and rock.
With the plane heated beyond re-crystallization temperature, the landmasses seem to sag under weight when they have high metal content. Sometimes, adventurers fall into puddles of molten metal that looked exactly like the burning hot ground around it. On masses with a higher ceramic or igneous rock content, the frigidity of the formation often makes it possible to imbalance its contents. It is not uncommon for such a thing to flip over, sending adventurers to their dooms below.
The weather is prime for the formation of metamorphic rocks. Growing in jagged spires jutting from the ground, multitudes of gems and beautiful stones pierce the sky around it, threatening to skewer those greedy enough to take from them. Often times the unsure footing of the plane is exploited by its inhabitants, integrating it into their fighting tactics or daily life. Azers sometimes tip smaller islands while someone stands on another side, sending them through the air akin to a seesaw. Flying creatures often try to flip entire landforms while creatures are on them, sending them tumbling down into the core, or loosing them from their hiding places.
Out of all the major elemental planes, Muspeil is arguably the hardest to survive in. Wildlife is limited, and what wildlife is there is highly adapted to the environment. On the ground, creatures have developed claws for gripping the ground or burrowing into the hot rock. Combined with their lightweight hollow bones, and their natural agility, they hold to the ground extremely well. Some learned to swim in the magma pools, using overflowing streams to move horizontally.
In the skies, creatures have taken flight. They can afford denser bodies, as hot gas helps bring them upwards. So while some use traditional wings, it is dutifully obvious that they adapted to instead use parachute-esque apparatuses to allow for perpetual flight and grant tireless balance. As such, there are some creatures that never land in the Domain of Fire.
The Domain of Earth, Grumen, is a barren place. The high concentration of elemental earth, while not being innately dangerous, has overtaken the land and left no room for vegetation. Additionally, the sand has dried up the sky, and left the place in perpetual drought.
The surface of Grumen is steeped in a hefty layer of sand. Gentle breezes over time eroded the sand to fine powder. The rolling dunes is the full extent of notable formation on the surface. Adventurers there are hit hard by the lack of available cover, leaving them exposed to the elements over the course of their journey.
Additionally, the land is devoid of water sources, making it a major concern for the unprepared. Travelers empty their canteens in mere days and are left to wither away. The desert-like sands also change temperature in constant intervals, hot during the day and freezing into the night.
The underground has been excavated into vast networks of tunnels. It is here that sentient life flourishes, turning cavern walls into living space and sturdy rock into operational platforms. Sometimes, the digging comes too close to the surface, leaving large amounts of sand prone to falling in at even a moment's notice.
There is little life on the surface of the planet, due to the lack of water and unpredictability of the climate. What does live on the surface must be adapted well to low resource environments. Many can store water for many years without another drink. Others have learned to pull groundwater from the earth, causing it to spring up in wells.
However, most creatures of Grumen instead create burrows in the earth. Many are talented at recognizing disruptions in the ground, sensing tremors from very far way. Their expertise in digging tunnels allows them to entrap unsuspecting creatures and draw them into their habitats. Many have been used by the workers of Grumen to achieve certain jobs, such as carve out irrigation routes or relay written messages between distant allies.
Ysil marvels onlookers with the exquisite beauty of its atmosphere. From off the planet, the gases and clouds create a green-grey marble effect, like a giant crystal ball. However, none should be fooled by this facade, as elemental air is not nearly as harmless as it may seem. Ysil can easily prove to be among the least survivable of the planes.
Elemental air can take many forms, but on Ysil, it takes its purest form. The atmosphere on Ysil is similar in content to that of the material plane- roughly 80%N 20%O with traces amounts of other compounds. However, elemental air is so abundant that being held within the constraints of gravity has condensed it to absurd pressures.
When things reach high pressures, it changes their thresholds for maintaining thermal energy, making it a simple matter for the the temperatures of everything in the plane to skyrocket. Additionally, metals and other materials might suddenly warp or deform due to the change in its chemical properties.
Big metal structures dot the plane, as well as floating stone landmasses which drift aimlessly in through the air. They say the metal towers are the result of a powerful group of beings making a system of bases from which to rest from space travel. They harness the air for processing, which can be used for breathing even outside the atmosphere.
Save for the humanoid races in Ysil, the majority of creatures are skybound. Almost all life here has an aptitude for resisting high barometric pressures. That way, they aren't collapsed by the constant force of elemental air. Additionally, most have extremely dense bones compared to similar creatures in order to let them pass through thick walls of air without being thrown about. As such, many creatures in the Domain of Air would be rendered immobile in the material realm.
There are not many land creatures in Ysil, and what land creatures there are tend to be small rodents who burrow nests into stone outcrops. Their complicated tunnel systems allow them to move easily around the stone without fear of being whipped off the rocks by wind currents. Some are even clever enough to manipulate the currents, making wind tunnels that can be used offensively in a fight.
Wynt, the Domain of Ice, orbits both Unseve and Ysil. As a result, heavy precipitation on the moon had turned to snow, and eventually filled the globe with a thick layer of snow. Below the snow, the planet is mostly composed of ice. Some abnormalities in the formation of this ice led to mountains and caverns that dot the landscape in awe-inspiring shows of natural beauty.
Ezer orbits Ysil and Muspeil alternately. The surface of the moon is mostly carbon based, surrounded a hot nickel core which heats the ground. The hot ground combusts into rising pyres of flame, letting out thick black smoke which now fills the atmosphere. The smoke while extremely hot rises, and when cold, it sinks into a thick, unbreathable cloud that menacingly obscures the surface.
Linj is the product of a shared orbit with Grumen and Unseve. Surprisingly habitable, the moon of ooze is often compared to the jungles of the material realm. Its humid climate is close to that of a jungle or swamp, making it the perfect environment in which wildlife can flourish. It is a lush green, and is full of creatures from the underbrush to the canopies. Some say that blobs emerge from the water to swallow people whole- but that is just a legend, probably.
Urg, which orbits Muspeil and Grumen, is mostly surfaced by thick slag. What seems solid at first glance needs only a touch to turn it to hot, glowing fluids. Like an ocean, the molten surface of Urg flows and even has currents. Some even say well-adapted creatures live within its wake. Some even say there are petrified civilizations at the bottom of it. Floating on its surface, stray efreeti and salamanders build cities that can wade in the magma safely, giving them a domain on their moons as well as on Muspeil. However, this cities can sink, and often do.
Infiyt, much like Ysil, is mostly composed of atmosphere. Vertical columns strike high into the air, and a small core at the center made of iron attracts electric sparks from overhead clouds. The coursing electricity is said to supercharge anything it comes in contact with. The tumultuous storms of this planet are often the source of massive tempests in another planes.
Niff's tie to negative energy caused the atmosphere to degrade to antimatter. As such, the whole moon had become a sort of attractive force in which things that get too close are annihilated. Niff could be described as a vacuum within a vacuum, and thus achieves a feat nowhere else possible in the universe- controlled destruction of matter. Matter annihilation results in energy, making the moon glow brightly at its event horizon.
Like Niff, Azzelyf glows extraordinarily bright, though for other reasons. The fires there were infused with positive light, crystallizing them to a giant mana crystal. It is said that when a god dies, their divine power is somehow returned to the light of the moon. This is simply fable, but alas there may be some truth to it.
The negative energy of Sihn smothered the fires, leaving behind only their remains. Sihn is nicknamed the Sea of Ash, as its surface is composed of the ash and soot of a previously hot existence. Some of the ash hardened to form solid land masses, though the ground they harbor is soft enough to dig through. The seas itself are like pools of fine ashes and thick flaky remains, leaving them hardly buoyant.
The elemental earth of Orgonutt had merged with positive energy, and resulted in a mass pressurization of earth into deep crystals. Some call it the miner's dream, as almost everything on the moon is actually a gemstone or crystal. Some crystals there exist only there in the multiverse, making it an aspiration to the greedy and curious.
The negative energy's antimatter failed to annihilate all of the elemental earth previously on Oukinlomu, so instead it resulted in making a big ball of fine dust. While the dust is usually quite settled, when anything interacts with it, no matter how small, it makes a large dust cloud that impairs vision. It is said once a comet scraped the side of the moon, and the resulting plume eclipsed Grumen for seven days and seven nights.
Positive energy raised the temperature of the oceans to unbearable levels, thus creating Thesyn, the moon of steam. A great cloud of steam was cohesive enough to stick together during the Cataclysm, so upon ejection to the Astral Plane, it was granted its own gravitational pull strong enough to pressurize the steam. Now, it is said that the core is steam so thickly layered that it can be tread upon without falling through. It is said to be the greatest source of perpetual power in the universe, and researchers have long sought to harness it for their own device.
The annihilation of the oceans on Thaum-Rygr left behind copious amounts of salt. In other words, it's a giant globe of salt. Despite its underwhelming composition, Thaum-Rygr is very unique, as salt is a prime material for dimension altering and thaumaturgy. Because of this, it often can interrupt the astral migration of aberrative forces and trap them within the planet's surface. For any paranormalist to survive the moon would be to uncover in depth research on almost any aberration known to man.