Prime World Gozon.
A First-Generation Prime World of the Orithyia Galaxy.
First-Generation Worlds were worlds created together with the formation of the Galaxy and were just as old as it.
While their sizes varied, these worlds shared key traits: immense mass, which resulted in stronger gravity (though this could be regulated by the World's Consciousness), an abundance of ambient energy, and they served as the homes of the universe's most powerful beings.
Prime Worlds and the like existed specifically to accommodate these powerful beings so they didn't go snooping around lower worlds that they could destroy just by kicking the ground too hard.
Among the First-Generation Prime Worlds was Aidos, an intergalactic hegemon on par with Gozon and the home world of Artemisia, Beatrix, and, in a way, Evan.
So, why did the Gozonians expand across vast distances without fear of losing their dominion to outsiders?