Reinventing the Plane of Air

This post collects some random ideas I had in the past for reinventing the plane of air. These are unfinished notes right now, but I hope anyone who reads this can be inspired to have adventures on the plane of air, or as I like to call it: "Cloud Cuckoo Land."

The Elemental Planes in General

The "material" planes, and by extension the elemental planes, may be generally divided into four broad levels of environment and locomotion: the sky of flyers, the land of walkers, the sea of swimmers, and the caves of burrowers. (There’s also the trenches beneath the sea.) Some of these environments overlap between the planes as one and the same, such as the ocean and the sea of water or the darklands and the caves of earth.

Elemental borderlands and the darklands

The places where the material and elemental planes overlap and form a single unit, allowing one to travel between them simply by walking (or flying, or sailing), are commonly known as the elemental borderlands. The most well-known of these are the sky, the sea, and the Darklands (Pathfinder's OGL name for D&D's under-dark), and some sages consider the planes of air, water and earth to be extensions thereof.

The planets of fantasy lands are not necessarily like real planets with crusts, lithospheres, magma and molten cores. Travelling down the strata of the Darklands may give this impression because these are technically spread through the material, earth and fire planes. The strata or zones are as follows (cf. Little Red Goblin Games' Races of Darkness):

• Twilight: transition between material and earth planes
• Dusk: wholly within earth planes
• Midnight: transition between earth and fire planes
• Deep Dark: wholly within fire planes

Travelling between the material and elemental planes is not limited to conventionally understanding of spatial geometry. A simple change in direction may result in an unrecognizable destination: a perpendicular turn at the dusk zone leads to the surface of the plane of earth.

Elemental animals

The flora and fauna of the elemental planes include counterparts of those of the material planes, ranging from identical to highly adapted for new environments. Unlike the SRD portrayal of the planes, these are generally not immigrants from the material planes (but those exist too). Depending on what you're inclined to believe, they either reflect the material like distorted mirrors or one group was created first by intelligent design/spontaneous generation and the other was created in imitation by divine fiat/morphic fields (or both are based on an abstract platonic template that doesn't exist in reality). These animals are specialized for their home planes and are generally unable to survive on other planes, explaining the relative dearth of interplanar invasive species.

Major geographical features of Cloud Cuckoo Land

Cloudscapes

City in the clouds

The landscapes of the plane of air are composed of semi-solid cloudstuff, which provides a foundation for forests, savannahs, castles and other diversity. The continents and islands float within the sky, sometimes travelling along air currents. Bridges of solid rainbow are a common route of travel: naturally occurring bridges are unreliable and appear or vanish unpredictably, whereas artificial bridges are as strong as stone and may be used to anchor islands together.

The flora include gigantic beanstalks, multicolored trees, and simple grass and shrubs. Some are unique to the cloudscapes: perpetually airborne plants held aloft with gas bladders, sentient fruit that flies to new places to take root, etc.

Giant beanstalk

The fauna are commonly capable of flight even if only to migrate between clouds; the idiom "do pigs fly?" is synonymous with "is the sky blue?". Herds of winged cattle and horses dot the plains while bats and flying squirrels flit through the trees. Birds and bugs are probably one of the few familiar things an adventurer will see here.

The preeminent races include the sylph, djinn and abasheen genies, aellar (winged elves), kestrals (winged halflings), wyndians (winged humans, identical to celestials in Project Ravenflight), and silfides or “air nomads” (yes, the guys from Avatar: The Last Airbender).

Aside: Information on the races I mentioned may be found in multiple sources. "Sylph" refers to at least two races, one found in The Slayer's Guide to Elementals and another in Pathfinder Advanced Race Guide. Aellar and kestral may be found in Dreamscarred Press' Bloodforge.  Silfide may be found in The Genius Guide to Races of Wind and Wing. Abasheen genies appear in the Tome of Horrors series.

In lieu of waterways, the cloudscapes have airways of liquid air. The rivers and lakes are inhabited by exclusively air-breathing counterparts of freshwater flora and fauna, such as boggards and locathah.

Skiff sailing the cloud lands

Sea of Air

Ship sailing the turbid cloud seas

The sea of air is exactly what it sounds like: liquid air, as viscous as water and breathable as air. Unlike the fresh air of the airways, the sea of air is fairly "salty" (for lack of a better term) and thus creatures from one may not survive in the other.

Sky whale

Aside from breathability, the sea of air is little different from any other ocean. It has fish, crustaceans, mollusks, reptiles, mammals, seaweed, and so forth. The intelligent inhabitants include exclusively air-breathing counterparts of merfolk, aquatic elves, tritons, sahuagin, deep ones, cecaelia octopus merfolk, and so on.

The Sea of Air is never deep enough to have trenches.

Sky whales

Fun Fact: The transition between breathing air and breathing liquid can be traumatic. Lungs are inflatable sacs optimized for air: learning to breath liquid may be frightening at first, while returning to air requires coughing up the remaining liquid. Gills are even worse off as breathing involves passively pushing liquid through them, generally by swimming constantly: any animal unable to pump its gills independently will asphyxiate just as if it had lungs with a punctured diaphragm.

Flying Seafood: The aquatic life breathe air, not water, and as a result some have flown from the seas and adapted to live their entire lives airborne. Similar animals may be found in the other elemental planes.

Sky rays

Undercloud

The interior of the clouds is home to a variety of burrowing life forms not unlike those of the Darklands. Whereas the Darklands present obstacles to breathing with poisonous vapors and confined spaces, the Undercloud is constantly aerated by the very walls of the tunnels. There is little plant life, but fungi are quite common.

Tunneling through the undercloud will eventually reach the glaciers of Underglacier.

The preeminent civilizations of the Undercloud are the alps (air dwarves, gnomes, azer?), jynxes (air goblinoids), and clow (dark elves/aellar with vestigial wings).