Hi,
i love rebellion and soase. the story is cool so far, cool enough to "live" every game i play. About this Vasari threat i think we wont get an answer, because they were talking about hints, right? That means as much as a clue?! No Answer, no epic telling or complete story. Ive don some of the ship-watching thing too, but i dont think it can be that obvious.
Whatever it was, it killed a whole fleet, whole planets and systems, without leaving a trace?! It cant be a ship or fleet alone, because that wouldnt drive the vas survivors so mad, that they cant describe it?! Must be worse i think. Else we would put up a titan fleet and drive it back to where it came from! So it could possibly be some catastrophic event, such as a growing black hole, that actually destroys universe, thus being absolutely inevitable and driving those who know mad. But then, how did they escape? On the other hand that could fit to the theory, that it all started in a lab, vas scientists create a big black hole, that gets out of control and kills all and everything. The cros sci-fi thoughts would be funny but from the side of stardock pretty uninspired.
I would actually love a clue about the way we can find the hint, because i want this answer 
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