Ego the Living Planet was first introduced in 'Guardians of the Galaxy Vol. 2'. Peter Quill(Starlord) finds out that Ego is his father and that he left his mom due to her cancer. Ego's true plot emerges wanting his so Peter to help contribute his Celestial power so that he can terraform the various planets he has visited, transforming them into extensions of Ego. Ego also reveals that he caused Meredith's cancer from fear that his love for her would get in the way of his plans. Quill turns against his father after the revelations, destroying Ego's avatar with his fellow Guardians. The Guardians succeed, and stop Ego's plans.