In the year 3761, what began as a simple plan to retake a strategic system from the Republic becomes the tragedy that brings humans and aliens alike together in an organized front against the Empire's ruthlessness. Devised by Zelevas himself, the plan involved the deployment of bioweapons previously used in experiments on backwater systems in a complete invasion of a densely populated system. Black Star spies discover the plot just hours before it is carried out, but arrive too late to prevent the tragedy of Gerbrand from occurring.
A densely populated system near the hotly contested border between the UUR and the UE, the system contained two large terran planets with agreeable traits and modest resources. The planet's main export had been population for the fleets, and had been largely unassaulted due to the rather strenuous nature of invading large planets that could be easily retaken, and that had no major shipyards to cut off. A single fleet was posted in orbit as modest protection, under the control of Commander Hexxan.
Days before the attack began, a high value informant spills small details of the Operations battle plans, but the intelligence is waved off as being a conspiracy and resources directed elsewhere during that time due to a particularly harrowing assassination plot against an Imperial Admiral. After the assassination's failure, Black Star operatives are put on the case, and information about one of the largest massacres in human history is discovered just hours before the assault. Unfortunately the operatives were delayed by half a day to preserve their covers, and the information arrives too late to be of use to the forces.
In the middle of the UE winter, a small Empire cruiser loaded with the most dangerous bio and nano toxins known to man enters orbit around Gerbrand II, the system's capital. The cruiser is cloaked in the most advanced stealth technology the Empire could afford, but it still deploys its cargo in a wide orbit about the planet. Within a few minutes, a second package is deployed against Gerbrand III, and the cruiser quietly slips back to safer shores. Then the deaths began.
The deadly nano-virus unleashed against the Gerbrand system was spread quickly and efficiently through the planet. The bugs were capable of corroding armour and clothing to get at the skin, which was quickly administered the toxin itself. The toxin and the virus replicated itself, and then spread to other victims. Within twelve hours the plague was trans-continental on both planets, and confusion and panic ran rampant.
The fleet in orbit was unintentionally sabotaged by the Commander himself, as Hexxan deployed soldiers to assist in bringing aid to the the planets under "attack" by the enigmatic virus. The soldiers were fully coated in protective suits, but the corrosive nano-virus pierced through them and infected most if not all of the teams.
At that time, an Empire fleet warped into orbit, and eliminated any resistance from what remained of the guard fleet. The fleet then took position and began bombardments against uninfected sectors of the planet, blockading any civilian craft from trying to flee in the panic. within 32 hours, the two high population planets were devoid of life, and the Empire was now in full control of the Gerbrand system
While the bioweapons were no doubt deadly and chaotic, the Empire had spent considerable amounts of time making sure each one was capable of being controlled and vaccinated against, so that once the planet was empty the nano-virus was recalled and new vaccinated colonists were allowed back in. A remarkably elegant and coldhearted way to go about capturing a system of several billion.
Operation Snowfall was a strategic success for the Empire, but it began a long series of diplomatic problems. Armed with the knowledge of Operation Snowfall's intent and scope, Black Star units passed the information into the light, and Sophon scientists began immediate research into vaccines, antidotes, and repellant suits. After Snowfall came to light, billions of Sophon and Republic citizens pledged their support to end the Empire's tyranny and reclaim humanity for the Republic.
While the Sophons had been allied with the Republic for some time, their support came mostly in the form of tech and resources. Now the entire Sophon fleet was dedicated to the mission, and were ready for battle. (Granted, large amounts of this support was due to fear of the bioweapons being turned on them, and eradicating the science stations they had in place on terran systems such as Gerbrand)
Despite the Republic's knowledge about the procedure, the Empire still chanced at trying their strategy again. Instead, recently deployed sensors around the similar Garusi system detected the Cruiser before it was in firing range. Stand by cruisers in orbit quickly disabled the ship while it was unaware of having been detected, and the bioweapons on board were brought before the Sophons as further test samples.