Who is Ego the Living Planet, Anyway? A Guide to Ego in the Marvel Universe
Ego the Living Planet was initially introduced in The Mighty Thor #132 (September 1966) and was created by Stan Lee and Jack Kirby. In this issue, Thor made a deal with the alien race known as the Rigellians, who were threatening Earth. If he could save the Rigellians’ home world from being devoured by Ego, they agreed to leave Earth alone. Naturally, the God of Thunder was victorious, convincing Ego to remain in the Black Galaxy and thus saving both Earth and Rigel from destruction. Ego’s creation came at a period in time where Lee and Kirby were largely focused on expanding Marvel's cosmic universe. In fact, this was also the timeframe where characters and concepts such as Galactus, the Inhumans, the Kree Empire, and the Guardians of the Galaxy (of course) came to be, mirroring Kirby's interests in experimental evolution and higher life forms.