Primordial Evolution Game/Tentouz

Tentouz are an odd species that posesses a lot of uncommon features. They look not unlike our earth cephalopods but are airborne methan-lifted, fire-propelled, gas-minded, acid-producing 8 feet high flying octopusses that have the most uncanny immunity-like methanervous system.

Biology of the tentouz:

An inside view of the metha-nervous system.

This part is a bit harsh with the technobabble, but as a bio student I couldn't resist to the challenge to make the chemistry work.

Behind the mouth, the food goes in a first stomach full of digestive acid produced by a liver/pancreas-like organ. The organic matter melts and the nutrients are directed to the lymphoïc system (it's not blood, it's a hemolymphoïc fluid that does not carry oxygen). The chime of all the unwanted matter then go to a second stomach full of a methanogen archaea (micro-organisms) flora (like cows but way tougher). This stomach is equipped with a valve that opens to spread the gas into the balloon providing them atmospheric buoyancy. The atmosphere being rich in oxygen, the methane gives a good buoyancy in the air. Tentouz can float 100km a day, and are able to do so safely at high altitudes.

At the bottom of the "balloon", all around the gas intake sprout, is a layer of neural cells. These cells are able to synthesize thousands of different neuro-transmitters. These organic molecules go back and forth into the gas chamber where they then exist in two different form, normal and the oxidized one with an additional acid function (R and RCOO-). The reverse methanisation (1) and the CO2 reduction (2) presented bellow are metabolized by the epithelial cells that cover the surface of the chambers (mostly on top).

(1) 2H2O + CH4 -> 4H2 +CO2 (incomplete reaction) | This reaction is constantly working in order to regulate the amount of gas and propulse the tentouz. The high amount of CH4 pushes it in the good way.

(2) NT (Neurotransmitter) + CO2 -> NT-COO- | The way of reducing a CO2 by adding an acidic function to a molecule is a pretty basic biologic reaction.

This oxidation liberates H2 molecules which are known to burst in flames in contact with oxygen. that's why the balloons burst if pierced. When the methylated form comes back to the brain cells, it is interpreted as an information.

The brain works by interpreting the variation of partial pressure of each neurotransmitter. All around the chambers are disposed small neural glands linked to the lymphoïc system. This allows to "save" some neurotransmitter in liquid phase when their partial pressure becomes high in the chamber. This is basically their memory. These glands are also able to deliver into the chamber foreign molecules that were taken in the stomach or synthesized by the organism or "saved" earlier. These can be colored molecules, bioluminescent molecules, toxins, neurotransmitters, etc. This allows them to adapt their color in order to communicate, confuse preys...

This system can also deliver into the back limbs to create the deadly bane-bubbles. The back sprouts only deliver H2 and surplus that bursts in contact with oxygen and then propulses the creature.

(3) 2H2 + O2 -> 2H2O + explosive liberation of heat. | Rather powerful in a O2 rich atmosphere.

Their air holes act directly as an interface to extract the oxygen needed for the cell metabolism and have the sense of scent. The oxygen is carried in a secondary system of actual blood vessels. This system does not ever enter in contact with the gas chambers.

They have also a basic nervous system to control their limbs and the various valves scattered between the gas chambers and stomachs. The back tentacle are carved by an extension of their stomach richly vascularized with hemolymph vessels and covered by mucus producing cells. That allows them to create acidic poisonous and flammable bane mucus.

The neuro-transmitter and their receptors on the brain cells are randomly synthesized by random gene splicing (that's the immunoglobuline synthesis way. Then, like the antibodies, these receptor can randomly be sensible to some foreign molecule. This causes to grant Tentouz with gradual immunity to poisons in contact with them allowing them to half-sentiently deal with it in their organism and use it. This molecule can temporally become a new "thought component". In fact sentience of the Tentouz depends on their ability to absorb various foreign organic molecules in order to complexize their minds. A starving Tentouz will become pale and get back to animal stage until it can feed properly again to wake up its mind and have back access to its dormant memory. The aging of the Tentouz is very slow, allowing them to last many years even in the dormancy stage.

The Tentouz have a very low mechanical power in their limbs. They can't lift great weights nor strike with strength. However, its four opposed tentacle digits are very dexterous. The Tentouz have the poorest audition. Their internal ear is almost entirely used for its balance keeping role.

Tentouz have a long lifespan (around 200 years if unharmed) and are unaffected by a lot of poisonous substances. They are hermaphroditic and reproduce by giving birth to a single larvae which have a long growth and needs a lot of nutrients. The Tentouz reproduce very slowly.

tl;dr: They fly with methane coming from micro-organisms of their stomach. Brain works with a pool of gas where all the neurotransmitter go. It can adapt with what they eat. They have colour shifting they use to communicate. They push themselves with a gas that burns in oxygen. They can throw bubbles of acidic poisonous mucus. If they starve they become pale and unsentient.