To my mind, the beauty of Sins of a Solar Empire derives from its comfort with ambiguity and room for interpretation. Players are free to participate in the story in a variety of ways, if only by dictating how their fleets behave during Sins games. With the exception of competitive multiplayer (in which culture and diplomacy are less efficient than orbital bombardment), players can choose to be ruthless warlords, gentle diplomats, or puppet masters. Victory can be achieved by inciting planetary populations to revolt, making peace with enemy leaders, or scouring enemy planets of all life.

It is possible to construct vignettes based on individual events in any given game. It's possible to interpret cultural overthrow of a planet as defiant citizens taking to the streets... or King Mob duped by propaganda. It's possible to imagine citizens of all three empires taking to their bunkers and shelters in the event of orbital bombardment. And it is possible to imagine the view from the comparatively calm bridge of a starbase or capital ship as battle rages around.

On a higher level, each faction is subject to interpretation. Are the Advent justified in their crusade, or are they genocidal lunatics?  Is the TEC the underdog or a sleeping giant? Are the Vasari little more then than the arrogant, decadent remnants of a stolen empire, or are they sympathetic in their obvious desperation?

In a game that asks questions like those above, it doesn't really matter what the Vasari are running from.  What matters is that they're here, they've been on the run for ten thousand years, and they're growing desperate as the stalemate continues. Though the policies and instruments of their fallen empire served the Vasari faithfully during their long journey, they are now faced with the unyielding TEC and the equally stubborn Advent.  Time is running out, and the Vasari must adapt or die. A schism is growing within the Vasari ranks: some wish to adopt scorched earth tactics, others want to encourage the TEC and the Advent to go into exile with them.

That said: though the above premise is sufficient to enjoy the game, it's still fun to speculate.

What we know:

• According to the opening cinematic, the disaster originated from a Viturska Imperial Lab orbiting the planet Kron
• Hereafter, we will refer to this lab as the Kron lab
• According to the cinematic, the Kron lab was dedicated to "experimental transport"
• Someone in the Kron lab  (by all appearances, a Vasari) pushed a button, which appeared to initiate the disaster
• The disaster took the form of streams of bluish-white light
• Incidentally: the streamers of light are the same color as phase space drives in a subsequent shot of a Jarun Migrator)
• The manual tells us that the disaster originated from the "inner planets" of the Empire and proceeded in waves
• The first planet to fall was probably Kron; the manual does not specify how many other planets fell along with Kron
• Three worlds went dark during the second wave of the disaster's expansion
• The Vasari homeworld was lost in the third wave
• The rate at which the Vasari lost worlds to this disaster is greater than the rate of the Dark Fleet's expansion
• Vasari analysts dismiss a rebellion, since a coordinated assault on so many worlds is astronomically unlikely
• After the third wave of worlds went dark, the Dark Fleet was recalled from the Empire's frontier and massed for a blind assault on the inner planets
• One warship (type unknown, hereafter known as the Survivor) survived the assault, emerging from phase space at a colony on the imperial frontier and showing signs of heavy damage; boarding parties confronted a battle-hardened crew driven mad with terror
• It is unknown whether or not the crew of the Survivor were literally insane, or whether or not they eventually calmed down. There is a world of difference between panic and literal loss of higher cognitive functions
• The manual does not specify if whether or not the crew of the Survivor was ever debriefed, and, if so, if anything was learned from them
• The frontier colony decided to relocate temporarily, leaving warning beacons behind; when the beacons went dark, they picked up stakes and took off.  They've been on the run ever since, whatever is following them only a generation behind

Points for consideration:

• As the disaster emerged from an Imperial transport lab, we can assume that the Vasari were tinkering with some new phase space or FTL communications or transport device
• Regardless of the nature of the disaster, whatever it was led to physical damage of Vasari ships, so it wasn't a purely supernatural or paraphysical phenomenon
• This damage could easily have been caused by Vasari ships opening fire on other Vasari ships
• The damaged Vasari ship aside, we don't know what happened within the core worlds besides a massive communications blackout.

Premises and conclusions:

1. Given Vasari mastery of phase space, plasma weapons, and nanoengineering, it's unlikely that the Vasari were pursuing research in these directions, with the exception of phase jump inhibitors
• According to the manual, phase jump inhibitors are alien artifacts; the Vasari don't understand phase jump inhibitors; they can only replicate them via nanotechnology
• The Vasari used phase jump inhibitors as part of their "subject containment network."  Translation: the Vasari used strategically placed phase jump inhibitors to slow down any rebels who somehow gained access to ships
2. Given both the expansion of the Empire and the concerns of the Internal Intelligence over a possible rebellion, it is probable that whatever the Vasari were trying to develop, it would either aid the expansion of the empire, or the containment of rebels
3. Psychic powers exist in the Sins universe -- the Advent have both a collective emotional experience and the ability to use telekinesis and psychic domination; psychic powers can be augmented, amplified, or projected via Psitech
4. The Vasari do not evince psionic potential

Possibilities:

1. The Vasari combined self-replicating nanomachines and phase space drives (with a rogue artificial intelligence for bonus points), creating an ever-expanding wave of omnivorous, phase-capable grey goo.  An omniphage that can perform phase jumps!
2. A phase jump inhibitor disaster occurred: the Vasari were attempting to reverse-engineer phase jump inhibitors (to apply this knowledge for transport, communications, or both), and the experiment backfired:
• In experimenting with phase jump inhibitors, the Vasari inadvertently either summoned or opened a portal permitting the creators of the phase jump inhibitors to return, with a vengeance
• Many thanks to Lord-Vale for this suggestion!
• Something locked away within a phase jump inhibitor escaped due to Vasari tampering
• If phase jump inhibitors are Psitech, then phase jump inhibitors could very easily contain a psychic entity of some kind
• A Vasari-manufactured phase jump inhibitor prototype malfunctioned and unleashed a chain reaction, such as a runaway phase space field
• This is unlikely: a runaway phase space field would destroy not only ships, but planets and stars; there is no evidence in the manual of stars disappearing -- you'd think the Vasari would notice that!
3. A psychic disaster occurred: having reached the limits of conventional engineering, the Vasari were experimenting with Psitech for communications or use in phase space transport purposes (or both), yielding unexpected results:
• A runaway psychic shockwave capable of driving people insane, or producing conditions that are utterly terrifying
• Reminiscent of the psychic noise generated by the Markers in Dead Space
• An out-of-control mind-control field intended for the subject containment network
• A mind-control field would account for the battle damage to the Survivor's hull: as ships fall under control, they open fire on their cohorts
• The birth of a gestalt psychic being or hive mind that grows by assimilating individual consciousnesses
• This would also account for the aforementioned battle damage: as warship crews were psychically assimilated, they would turn on their fellows
• The Third Impact, Convergence, the Rapture, Childhood's End, whatever you want to call it: everything in the path of the disaster ascends to a higher plane of existence. Traumatically.

Regardless: I'm convinced that there is no conventional solution to whatever the Vasari have unleashed.  I feel that the only way the Vasari can survive is by acknowledging the Advent and the TEC as peers, calling for a cessation of hostilities in the face of a greater threat (after all, are the Advent and the TEC willing to bet their lives on the possibility that whatever is following the Vasari is hostile only to the Vasari?), sharing all the information they have on the anomaly, and making a stand against the threat -- because I'm pretty sure that if Advent Psitech, TEC industry, and Vasari engineering can't beat this thing, nothing can.

• The Advent are necessary to understand the problem and propose a solution
• The Vasari are necessary to design the solution
• The TEC are necessary to reproduce the solution en masse

After all: sooner or later, the Vasari will run out of places to run. What better time and place to stand their ground than with the only two races in their history to give them pause?

What say you?