Melaxni are massive space-borne creatures, which reside within most known Fields of the Palioxis Starfield. Melaxni have existed in some form for a billion or more years, presumably before any major species rose up in the region.
The origins of Melaxni are completely unknown, but depictions of them in ancient scriptures and texts on many worlds show that these species have likely been around for 1.27 billion years. This makes Melaxni one of the most successful organisms, and are clearly able to live very long lifespans.
Potentially, Melaxni can survive for over 1.3 million years, mostly in a hibernation state. Active Melaxni live relatively shorter, with the oldest confirmed active Melaxni living for over 19,000 years. Theoretically, natural Melaxni can survive for up to 20,000 years while being active, but this has not been recorded yet. Genetic technology can also change this.
Melaxni have a relatively simple anatomy for a creature of their size. Melaxni are normally covered in a tough leathery skin and have silky hair on top. Melaxni don't have complicated eyes, but they do have simple light receptors. Melaxni also have a complex 'ear' system that allows them to hear at a higher level. Long-range and high-frequency electromagnetic waves, like as radio waves, can be detected by this ear system.
Melaxni's skin is highly resistant to space debris, and it have been known to withstand small objects moving at great speeds. A Melaxni's skin can also endure extreme heat. Melaxni's skin protects a tough system of entrails that operate together in a system of organs.
Space's zero gravity has also allowed for a richer organ system and new techniques to maintain it. The stomach of a Melaxni, for example, functions by establishing biological high and low pressure zones that store food and let it to enter and exit. This happens on its own, thanks to the hydrogen that a Melaxni can store. In a Melaxni, hydrogen, helium, and other vital gases are stored in a giant retractable sac that also functions as a mouth. Small airtight apertures take gas and, with enough of it, can create pressure. This circulates throughout the body and satisfies the Melaxni's nutritional system.
Melaxni can travel and transport themselves using gasses, most notably hydrogen. There are two 'exhausts' at the rear that can burn hydrogen and use it as a fuel. In certain circumstances, extremely complex biochemistry and genetics can produce a natural sublight bio-drive, which can reach near-light speeds. This is the Melaxni's principal mode of long-distance transportation.
Melaxni possess a delicate skeleton due to their robust skin and resilient muscles that shield them. There is not much of a need to move in a Melaxni, as well. Since moving in zero gravity is so much easier, bones are more or less tissue, surrounded by heat-conserving fat. These bones are not resistant to many types of gravity, but they can sustain the forces of planets with lower gravity.
Melaxni are considered to be docile, kind, and playful with other organisms. Many individuals have been harmed while researching Melaxni due to the force and toughness of Melaxni impacting their bodies. This has led to comprehensive research on these creatures, which is usually conducted on young Melaxni who are not as dangerous as adults.
Melaxni can be extremely hazardous once turned agitated. Even m etal can be crushed, broken, and torn by their massive, strong bodies. They're extremely difficult to kill, despite their low Intelligence. The destruction of the brain is one of the only effective ways to kill a fully grown Melaxni. Another approach to immobilize it is to deplete its blood supply to the point where it becomes completely paralyzed.
Melaxni can also be quite hazardous if they become enraged, as their exhausts can reach extremely high temperatures. Melaxni has been known to weaponize these exhausts, causing damage to ships in the procedure. Melaxni can also crash into spacecraft deliberately, causing significant hull damage. Larger Melaxni can be intimidating to vessels and their crews, although they are rarely enraged.