Atlins
The Atlins are an amorphous intelligent species native to Eos. Descended from the remnants of Gehenna, the Atlins are a plasma-based species more similar to single cells than complex life. Atlins possess no defined shape, taking up anywhere from 0.5 to 3 cubic meters of space. Within this space is a series of intricate chemical reactions involving large numbers of charged volatile enzyme complexes, magnetically charged particles, and soot-like carbon molecules floating within a medium of hot gas and plasma analogous to fire. Because of this high-energy environment, these particles collide and interact constantly.
Atlins have been very active in history, spreading to occupy all the Icaran Ring of Eos. As they left Eos' gravity well to explore the stars, their society became the bedrock on which the Triumvirate Civilization formed. So large was this civilization that nearly every living Atlin served in its bureaucracy. At first, they also served as soldiers, but their intolerance of cold and oxygen made them less suitable for temperate oxygen-rich worlds. The collapse of the Triumvirate forced the Atlins to spread across Cosmoria, forming many nations. Today, the Atlins are highly involved in the Greater Martial Consilium. Their unique biology tends to create societies of entirely Atlins, such as the great city of Karaos. The Atlin city of Lowa, Eos, became a multi-species settlement. A result is the religion of Ibaradism, one of the most popular around, spreading from Atlin cultists to the entire universe.
Biology
The Atlins exist within a medium of hot gas and plasma that takes the role of the "solvent." By mass, Atlins are mostly carbon dioxide. Other gases include sulfuric acid, nitrogen, fluoride compounds, and trace amounts of Xenon. Almost all of these play minimal roles in biochemistry.
Enzyme Complexes
Most of an Atlin's dry mass exists in "Enzyme Complexes." Enzyme complexes are immense molecules several million atoms in size, and, like proteins, carry out all biological functions. Atlin ancestors emerged on Frechlecht, simple organisms made up of aerosolized enzymes. As they evolved the means to control magnetic fields, the complexes began "cooperating," forming regions of dense concentrations of molecules. They evolved ever-increasing temperatures to speed up their metabolism. Atlins are related to analogies of all types of fire, including immense diffuse regions in the atmosphere similar to aurorae, embers floating in the air like plankton do in the sea, balls of lightning whizzing through the air, or microscopic sparks. The Atlins exist in an entirely different paradigm to most life forms.
Structure
Atlins, were they made up of pure fire, would have no form. A crowd of them would instantly become one contiguous entity. The way they maintain their structure is through the use of controlled magnetic fields. Near the Atlin exists an "exclusion field," like a cellular membrane it serves to keep foreign substances at bay. This field can expand or contract based on a dynamo of much hotter plasma in the Atlin's core. As charges cycles through, this central magnet maintains this field.
Suspended on an Atlin's surface is an ever-changing skin. This skin is mostly composed of metal ions. Anything could end up caught in the exclusion field, including potentially dangerous substances. Pathogens, toxins, and even dirt are a constant threat. Embedded "neutralizers," enzymes capable of removing charge, tirelessly clean the exclusion field.
Magnetite Manipulators
Small dynamos exist throughout the Atlin, allowing for movement, changing shape, tearing apart food, and manipulating objects. When it came to moving inorganic objects, however, just the dynamos would be useless. This is what the Magnetite within them is for. A cloud of Magnetite particles can envelop small objects and move them with little effort. Most Atlins in the modern day use gloves, magnets arranged in the shape of hands. This advancement greatly increased their ability to form civilization.
Communication
Atlins are capable of producing both sound and flashes of light as a means of communication. Sound is produced by charge differentials built up within the Atlin arching across small distances, creating pure sine waves at precise wavelengths. Words are spelled out using the 12 different tones they can naturally produce. Just the words, however, only convey about half of the meaning contained within the Atlin language. The other half is supplied by colors created by concentrating certain chemicals within their centers. They can produce six different colors, red, yellow, green, blue, cyan, and indigo to add to the words they are speaking as six additional "syllables" that could be produced.
Written language, consequently, requires both color and symbols to convey, although many scripts only have one or the other and depend on symbols to convey color or color to convey tones.
Nervous System
The Nervous System is by far the most complex part of the Atlin. Their "brain" exists distributed throughout their entire body with every enzyme complex also serving as a part of it. Signals are transferred not through electrical signals but through weak shock waves emanating across the organism. These shock waves are consequently modified, re-emitted, and "interpreted" by the various enzymes. Usually, they signal for changing enzyme shape but can also signal for the enzymes to act on the dynamos or other charged particles within the Atlin.
Sensory Organs
Sensing sound is simply a matter of absorbing vibration from outside. Sight, on the other hand, is much more complicated. Certain compounds are embedded within the containment field which react to different energies of light. Capable of detecting well over one hundred distinct colors, the range of "sight" overlaps significantly with detecting heat, cold, ultraviolet light, and other forms of radiation. Modern Atlins have modified themselves to see radio waves, allowing for easy communication with ship systems, machines, and other devices.
Smell, equal to sight in importance, works essentially the same way. Enzymes capture volatile particles in the air and use them to signal the rest of the nervous system. All Atlin senses exist as one "super sense," which for them is similar to experiencing a sort of sight. Everything is perceived as one of thousands of colors, and most objects are bathed in hundreds of colors.
Cognition
Cognition is carried about mostly within the central dynamo by a very dense array of enzyme complexes whose sole purpose is acting as a brain rather than other tasks. These enzymes are some of the largest within the Atlin, with many forming rings, chains, and even macroscopic spheres whose internal vibrations are capable of minute data processing.