What specifically are you curious about?
Physically, they're rocks. Rocks who want to make it BIG. They engineer on massive scales, they're loquacious and dramatic, their technology is probably the most advanced in the game, and their proud in both senses of the word. Them not being playable means that they're even more alien in their objectives and culture than the Zenith or Evucks.
They're really important to AI War, and most of the history we have about them relates to that game. Means it's probably not relevant to SBR, except what that history says about them as a race. I can post what I know, the relevant content is in Fallen Spire, Ancient Shadows Nebulae, and the Exodian Blade (though I haven't finished the nebula orz)