Stardust was once known as the Ethereal Lambda-Zero, but became a Herald of Galactus and was bestowed with the Power Cosmic. She already possessed numerous powers as an Ethereal so her empowerment by Galactus made her one of the most powerful cosmic beings in the universe. She was immensely brutal and would slaughter any being who tried to escape the planets her master consumed.

This wasn't something that bothered Galactus all that much, but it gained the attention of Beta Ray Bill who was attempting to save the Korbinites on New Korbin, which Galactus was consuming. That paled in comparison to her actions during Annihilation. When she finds that the Silver Surfer returned to his post, she offers the remnants of her own race to regain her position, which is something no Herald had ever done before.