Aegis had lived in the universe since it was young. She was tasked with sorting out the divergences of the living universe. She destroyed all of the chaos mites that Diableri created. After the Proemial Gods lost their battle with Galactus; Aegis and Tenebrous were the only survivors and they were imprisoned by Galactus at the edge of the universe.
During Annihilation, She and Tenebrous were set free by the destruction of the Kylny caused by the Annhilation Wave of Annihilus and made a deal with Thanos to capture Galactus together.