Setting

4961: The bloody genocide that would came to be known as the Emperor Wars is at its fifth years. By now, all major Houses are involved in the conflict, and precious few worlds are left untouched by the ravages of war.

The Acheron system, a world controlled by House Hazat but sitting dangerously close of the Li Halan border, is not spared and is viciously fought for. Things only get worse when the key to a previously locked Jumpgate is discovered. On the other side of the Jumpgate, the first Hazat exploration expedition discovers, is a solar system made of five lesser planets and two gas giants. And a second Jumpgate.

The Li Halan see the newly-discovered system as a potential foothold in Hazat territory, easier to take and defend than heavily protected Acheron.

The Hazat see it as an unexpected source of raw material for the Acheron industries, bled white by the war effort.

All Houses see the second Jumpgate as a potential trump card that cannot be afforded to be left in anyone else's hand.

Within two months of the Jumpgate's opening, the Li Halan have acquired the service of Charioteers holding the gate's keycode. The fight for Acheron escalates and becomes a fight for the new system, christened Thrinakia.
4963: The fight for Thrinakia goes on. Of the five lesser planet, only one is propice to human life. It is, however, an aquatic world; a global ocean covers its entire surface, leaving only scattered islands for human to colonize. The planet harbors a local amphibian sentient species, but the too scarce contacts with the Hazat settlers revealed precious little about them.

The Li Halan forces, taken by speed by the Hazat for the control of the aquatic world, established themselves on one of the moons of the gas giant closer to the jumpgate leading to Acheron. The moon, almost big enough to be a planet by its own right, possesses a breathable atmosphere, but is a cold, barren wasteland. The colony is a calculated gamble for the Li Halan. Its location gives it strategic advantage over the Acheron Jumpgate, but its dependency over external supplies makes it a very precarious beach-head.
4965: The Li Halan battle cruiser Su-Yari is the last recorded ship to enters the Jumpgate. Six days after her crossing to Thrinakia, the Jumpgate shuts down. The efforts of both Houses' Charioteers and Engineers prove to be futile; the Jumpgate remains silent.

As months pass, the Houses come to consider Thrinakia as lost to the Known Worlds. All souls left stranded on the far side of the Jumpgate are written off as casualties, and the tides of war move to lick other shores. Years pass by, the interest in the Thrinakia Jumpgate slowly ebbs away.
4998: Thirty-three years after the passage of the Su-Yari, sensors on Acheron Prime pick an energy outburst from the outer region of the system.

The jumpgate to Thrinakia has returned to life.

Two weeks later, the three scout ships sent to investigate intercept one of the Hazat escorts reported lost more than three decades before. Inside, a grim crew of eight mummified corpses.

Things have changed as much as they remained the same. The Acheron system is now under the control of the Church. The Emperor Wars are over, and the Li Halan and the Hazat are, at least officially, at peace. But as soon as the Jumpgate returns to life, revendications are made for the lost world of Thrinakia by Houses Hazat and Li Halan, as well as by the Church.

The matter is brought up to the Emperor. After many excruciating months of negotiation and bitter bickering, the imperial court gives its verdict. The system shall be under Imperial control, but all three involved parties shall be given jurisdiction on a fair share of its worlds.

A scouting expedition is organized. Lead by an imperial inspector, it includes including representants of all involved parties as well as third-party neutral observers.
4999: On the first day of the year, the Imperial frigate Steppenwolf, flanked by the ships Raphael, Satori and Ascension feed the Thrinakia Jumpgate with its activation code.

Minutes later, all four ships have left the Known Worlds space.