Dread Lord War
The Dread Lord War was a conflict between a coalition of younger races against the Dread Lords.
The conflict was born out of tensions between the Drengin Empire and a coalition of other races united to oppose them. These two forces maintain a status quo that was suddenly broken by the Drengin's surprise attack against the Arcean Empire. Seeking to further their goals of defeating their ancient enemy in the Arceans and their allies they aggressively sought Precursor artifacts. Despite the efforts of the Terran Alliance to stop the Drengin from acquiring too many of these powerful devices the Drengin were able to put one to use, the result was that they released the Dread Lords from their pocket universe prison. The Dread Lords immediately attacked the other races, including the Drengin, beginning the Dread Lord War.
The Drengin refused to combat the Dread Lords, even as their worlds fell. However, a coalition of factions led by the Terran Alliance rose to meet the threat. In a massive battle the coalition was able to destroy the main Dread Lord force. However, it came at a heavy cost and seeing this weakness the Drengin, now allied with the Yor Collective, entered the conflict and attacked the weakened coalition.
The Torians and Arceans both fell to the Drengin and Yor, leaving just the Altarians and Terrans. Earth, on the brink of invasion, was sealed behind a Precursor shield and the Altarians threat of mutual destruction for invasion of their homeworld saw it survive. However, the colonies of these nations were not so fortunate and the Drengin and Yor destroyed these worlds.
The Drengin Empire's conquest was paused as it fell into civil war thanks to Dread Lord interference. In this respite the Terran 2nd Fleet was able to locate a surviving Arnor and convince him to aid in finally defeating the Dread Lords. The Dread Lords finally met their end when the Terrans used the Terror Star to destroy the star system that was home to the Dread Lords.
With the Dread Lords finally defeated the Dread Lord War finally came to an end. However, the galaxy was still a hostile place with the Drengin and Yor supreme. They continued their destruction of the Torian, Arcean, Altarian, and Terran empires