Short: Mind dust, braiding their possession with living network. Can be transformed into any objects, while "structural mimicry mode" is active. They live in lines between the planets and being in deep symbiosis with minor factions.

Background:

Creating and updating Log:

Error 1: undiplomatic amoeba told joke in bar about birds love to shining jewels in presence of Hissho.

Error 2: Leaving body, amoeba took control of his warship in orbit, in thirst of revenge entered wrong coordinates of bar, and took shot.

Error 3: Missile overshoot bar and hit ancient artifact that has awakened us.

Error 4: All galaxy fearing our expansion has stopped contact with us,  declared that we are enemy and sealed us.

Error 5: All of Horatio Group, which develops our deterrence system, allowed same error in design, which led to fall of protection and absolved us.

Error 6: Conquered planet and overcome its gravitational pull, we labeled all galaxy races as dust slavers, and go to war against them.

Error 7: Incorrect calculations of durability of ships and ground units form from dust brought to parity in war. Result - Peace.

Targeting: search for causes of past errors, objective of creating; symbiosis with weak beings, peace with strong beings.

ReHello World.

Gameplay

• Planet Population growth depends on food and consists only minor factions. Number of lines to the system, trade routes, planets routs in system gives bonus to the dust and science (more population of Pollen).  (\or just show pop of pollen as usual, if its difficult)
• Structural mimicry mode - ability to instantly create any (or Combat only) units from the dust without using production, paying only dust. Such units are not eternal, and have a limit of life, after which dust back on treasury.  Since dust is their processing power, activation of this function entails - n% of science during mode is active.  Trading dust outside the event entails short-term penalty for happiness. Any strategic resource can be made from dust at the  time of events, with lower expense of dust than it price at market. 
• Empire obstruct the movement of foreign and neutral fleets on its own and Alliance territory, allies gain bonus movement. 
• In case of war, the enemy pulled out percentage of income dust. In case of alliance, it gives all members bonus of dust and science.

Advantageous for Alliance and strong in immediate defense, but dusty army is ineffective in attack, as the short-lived. I hope mention negative attitude to all factions does not break the rules.

P.S. Originally wrote text for quest, so i can reveal in comments fraction, who had organized dust activation and further releases (for clarity. there was clue in log:), and sorry for second reference to Hyperion :)