Big Three

For a brief period of time between the Nul petitioning for membership and the Shiss Hegemony being destroyed, the three largest societies in the Milky Way Galaxy Union, Galactic Council (Kermac), and the Shiss Hegemony were known as the Big Three.

This didn't last long since the Shiss and Union entered a war that utterly destroyed the Shiss Hegemony, leaving the Union and Kermac as the Big Two. That also didn't last and the Union acquired the nickname "Big One."