With the arrival of Unbidden forces from the extra-dimensional realms, units of the Greater Terran Union fought a largely defensive campaign amidst the ruins of the Florian Matriarchy, confident in the belief that the hostile entities were incapable of traversing the L-Gates into the the extra galactic cluster controlled by the Union.
This belief was proven to be false following the advance of the Unbidden upon the L-Gate in the Gethouri black hole. A force of 80,000 points on the fleet command rating scale invaded the Styx system of July 16th, 2650, marking the first sortie of unbidden forces in the territory controlled by the GTU. In there path was the 4th Expeditionary Fleet which had been assigned to cover the terminal egress of the L-Gate system. Protected by the fortress of Styx, the 4th Expeditionary managed to successfully fight off the initial unbidden assault, only to be engaged a second time by another larger force.
By this time, fleet intelligence had detected a massive build up of Unbidden forces in the galactic south, aimed directly at the L-gate to Styx. The objective of the extra dimensional invaders was clear. The destruction of Styx fortress and the seizure of the terminal egress. Should they prevail, the Ubidden would gain access to all sectors of the Milky Way and the heart of the GTU. Sol.
As July 2650 turned to August, two more Unbidden fleets engaged the 4th expeditionary who was becoming rapidly depleted in numbers. The High Marshalls, having realized the enormity of the danger facing both the GTU and the Galaxy, ordered the immediate deployment of the entirety of fleet command to Styx to head off the oncoming disaster. On September 10th, 2650, 3 more Unbidden fleets entered the Styx system to reinforce the two already engaged with the 4th expeditionary, raising their combined strength to 250,000 on the fleet command rating scale. In desperation, the commander of the 4th expeditionary ordered suicide ramming attacks against the Unbidden, effectively ending his units resistance in a final blaze of defiance.
With the destruction of the 4th expeditionary, the Styx fortress lay open to the Unbidden who rapidly moved to seize the system as the terran defenders on the gun platforms prepared for a final fight to the death. It was at this point the Warband of the Great Khan, led by the Khan of the Talakur Khanate himself, unexpectedly traversed through the L-Gate. Called to battle in the memory of the Great Khan who had centuries ago created their nation, the Talakur fleet launched a desperate and ultimately futile suicide charge against the Unbidden. Their sacrifice was not in vain however, as the Unbidden were forced to pull away from Styx Fortress to engage them. The delay was pivotal as by the time the Unbidden had managed to reorganize and once more advance upon the fortress seven Fleet Command battle groups led by Ryan's Raiders and the Terran Home Fleet arrived in system and engaged the unbidden forces under the guns of Styx. Between the two sides there were nearly 1 million points on the fleet command rating system in a battle that lasted all through the month of October 2650 that resulted in an overwhelming terran victory. Though a victory at great cost and the sacrifice of several dozens ships of the line and more then 20 million dead or wounded, counted among which was the death to the last man of the Warband of the Great Khan and 4th Expeditionary Fleet of the Greater Terran Union. The Sacrifice of which would never be forgotten by the GTU, nor the galaxy as a whole.
The defeat of the Unbidden at Styx marked a major turning point in the war and halted Unbidden expansion, allowing the GTU to launch a massive offensive that led to the relief of the Imperial Domains, which up until that point were facing extinction. On terra itself, a great bronze statue was cast in the shape of a Fleet Command Sailor, the insignia of the 4th expeditionary on his collar. At his side, for the first time memorialized by the GTU was an Alien. A Talakur warrior. Together they both raise a sword in defiance against some unseen foe. There is no caption to the memorial, because no caption is needed. All know what happened on that bloody month of September, 2650.