Biology:
Tholians have few, if any, recognizable internal organs. Their exterior is composed of a semi-transparent thick layer of crystal which has microscopic pores to absorb the gases naturally found on their planet and artificially created elsewhere and excrete the waste in the form of another gas through special excremental pores. On Tholia, crystals that grow throughout the planet produce this gas. In order to continue growing, the crystals require the waste bi-product that is naturally excreted by Tholians, similar to plants and their relationship with oxygen-breathing animals on Earth. Elsewhere, the gas is replicated through different life-support systems.

The emotional condition of a Tholian can be judged via the color their body emits, ranging from red for anger to blue for upset/concerned.

Since no Tholian possess external limbs, all Tholians posses a telekinetic ability that ranges from weak to quite strong. The strength is determined by the same method a humanoid's strength is determined. The more a Tholian practices their abilities, the stronger they become. The strongest Tholian mind can lift a small Federation shuttlecraft a very small distance, whereas the weakest Tholian mind (at "birth") cannot even hold its own body above the ground.

A bi-product of their strong mental abilities is telepathic communication. Since Tholians have no mouths, they communicate to each other through their minds. In order to operate any of their machinery, telepathic commands have
to be sent to computers that have been designed to pick up their form of communication. In effect, Tholian vessels are controlled by a Tholian mind and require far fewer crewmen and respond much quicker than other starships. When a Tholian's voice is heard, you are actually hearing either a computer simulation of their voice or they are communicating directly with the subject's brain. Tholians are not capable of reading the minds of other races, however; they can only broadcast their thoughts.

People:
Originating from their home world of Tholia, Tholians as a race are very prideful and arrogant. They possess advanced techniques in constructing with high-temperature metals, energy storage, and crystalline construction and the average life expectancy is approximately 2,000 to 4,000 human years. Tholians are a hive-mind, capable of communicating with the entire race at one time. They are also known for being extremely punctual and not appreciating tardiness in other races. Tholians are not raised by their creators, but by the government from birth until the Quilahra, "Age of Progression" (similar to the "Age of Ascension" with Klingons). The Quilahra is determined by the career the government has designated for the child and can last from 300 to 50 human years. The only career that cannot
be given at birth is that of diplomat. This career has to be earned through serving on the Assembly for at least 25 years. Since most Tholians are xenophobic and few in relation to the entire population serve on the Assembly, few Tholians serve as diplomats. Attempts by the other major Alpha Quadrant powers to either learn more about or actually infiltrate
Tholian society have proven less than effective, mainly because of their non-humanoid form and their preferred atmospheric conditions, which are too hostile to humanoids. Another reason that little is known about this race is that Tholians meet all incursions into their space with extreme hostility. Few vessels have survived a trip into Tholian space and all that is known from the long-range probes is that the core area of Tholian space consists of a large nebula in which new stars are forming.

Planetary systems
have been identified as usually very young with Class C, F, and H planets. The few expeditions that have returned from Tholian space have reported planets rich in mineral resources, but located within a vast region with a massive number of subspace anomalies, making it impossible at best at this time to conquer and control such an area. Tholians are also known for being opportunistic. They will seize small amounts of neighboring territory for no apparent reason and will begin guarding it as greatly as any of their other possessions. The systems that they seize are of no known value and it is not known by the Alpha Quadrant powers why they do this at this time.

Technology:
Tholian Destroyers are constructed from hyper-lineated crystalline-lattice materials. This allows for extremely durable hull structures. Their main weapons systems consist of phaser-like beam weapons, and Klingon-like heavy disruptors. Their main weapon, the Tholian Web, is constructed of tractor beam-like energy and requires more than one Tholian vessel to create. Once completed, the web can either crush an enemy vessel trapped within, or transport it to wherever the captors so choose. These vessels until recently had a sensory blind spot, which William Riker discovered in his Academy days and has since been eliminated. Since their Destroyer vessels are very resilient, Tholians construct only
this class of starship. The firepower of one capital ship would be approximately equivalent to the firepower of a small fleet of Destroyers and the Destroyers are easier to construct, making them the ship of choice for the Tholian Assembly.

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