An event caused Galactus, the Devourer of Worlds, to consume too much energy. When this happened, Galactus increased in mass, growing into a massive black hole. This black hole continued to grow, threatening the entire Andromeda Galaxy.
A device was made to attempt to stop this, a white hole bomb, that if successful would free Galactus and stop the expansion. Only Hercules was able to deliver the device. It was successful, but cost Hercules his life. But in the separation, Galactus also separated. A new being was born – Cosmos – the Bringer of Worlds.
Instead of destruction, Cosmos would bring life to planets, create new star systems and heal dying stars.