Trailer Shivan theory
As theorised by Stryke 9
Nah, I think this proves my theory that the Sathani are Shivan trailer homes. See, they really just wanted to make friends with the Terrans this whole time, but due to an unfortunate culture gap and some preliminary spy reports collected durign the Terran-Vasudan war, the Shivans figured our primary method of communication involved focusing high-density plasma charges into each other. Thus, Lucifer scout fleet showed up and transmitted the message "We come in peace", wiping out all nearby. Hurt and confused at the Terrans' and Vasudans' panicked flight, they followed the GTA fleet to Vasuda Prime. Knowing an important populated planet when they saw one, what subsequently ensued was the equivalent of thousands of years of Shivan history, science, and literature broken up into several easy-to-understand blasts...
Thirty years later, the Shivans spot Terrans in their nebula. Curious as to what happened to their peace delegation, they accost the first fleet they see and bombard them with questions. The Terrans return fire, and, overjoyed that contact has finally been made, the Shivans mobilize their colony ships, ordering them to set up a permanent base around the nearest Terran star where Shivans and Terrans (and Vasudans, who the Shivans assumed were just more Terrans) could trade, communicate, and live in harmony. Up to the death of the Colossus, the Shivans maintained their good intentions, though they had to admit that maintaining good relations with the Terrans seemed to be getting an awful lot of them killed. It was only when the Terrans sealed off the first Capella jump node that the Shivans guessed that something was amiss.
Slowly the idea formed that maybe we WEREN'T friendly, after all. Hurt by this possible breach of trust, the Shivans sent out one last delegate, headed on what they last knew as a route to the Sol system and the capital of Terran government, housed in a Cain class executive transport. When diplomatic talks opened up prematurely and destroyed the Cain and the diplomat before a meeting, let alone consensus, could be achieved. Shocked and disgusted by the treachery of the Terrans, the Sathanas fleet blew up the Capella star in the universal signal for "farewell", which they hoped would eventually reach the remaining Terrans in other systems, and returned home, never to be seen by Terrans again.