Ego the Living Planet Fact — November 5, 2026

Today's Fact

For forty-five years Ego believed he was one of a kind. Then the Stranger admitted the living planet was an experiment — and that the control sample had spent its whole life in a cage.

EGO HAS A BROTHER — A SECOND LIVING PLANET THE STRANGER BUILT JUST TO SEE THEM FIGHT!

The Featured Fact

For forty-five years, Ego the Living Planet believed he was unique — a single god-sized mind adrift in the Black Galaxy, the only world that could think. Then, in Astonishing Thor Vol. 1 #1–5 (2010–2011), the ancient cosmic being known as the Stranger told Thor the truth. Ego was not an accident of nature at all. The Stranger had created him — and he had created a second living planet as well. The twin was named Alter Ego, and it had spent its entire existence locked away in a pocket dimension inside the museum of the Collector, a living world kept as a trophy.

The second planet was the price of the first. The Stranger had needed the Collector's instruments and formulae to build a living planet at all, and the Collector demanded a twin for his collection in exchange. The Stranger agreed gladly, because the bargain handed him a perfect experiment: two identical worlds, one raised in total freedom among the stars and the other in total isolation and captivity, so he could one day learn whether freedom or captivity bred the stronger will. He even arranged for Alter Ego to hate its brother, so that when the two planets finally met, they would fight. Ego, overjoyed to learn he was not alone, raced across the cosmos to find his twin — and found a brother who had been prepared to destroy him.

The brothers collided near Earth, two living worlds tearing into each other while Thor fought his way inside Alter Ego's brain to stop the slaughter. Wounded and losing mass, Alter Ego was beaten back, and Ego was forced to strike in self-defense — but Thor intervened before the killing blow could land. Alter Ego broke apart, yet its fragments gathered into a moon, and that moon settled into orbit around Ego. The experiment the Stranger had designed to end in destruction ended instead in a family: Ego the Living Planet, traveling the universe at last with his brother circling him forever.

Why It's Obscure

A twin in a tesseract, a scientist inside a planet, and a second sibling who left home to party.

1966 debut

The face in the Black Galaxy — Ego first appeared in Thor Vol. 1 #132 (September 1966), by Stan Lee and Jack Kirby, when the Rigellian Colonizers hired Thor to stop the talking planet devouring their worlds.

The brain

Thor went inside him — in Thor Vol. 1 #226–228, Thor journeyed through Ego's body to his brain and learned his oldest origin: the scientist Egros, merged with his planet when its sun went nova.

Ego-Prime

A cutting that grew up — the Rigellian Tana Nile took a sample of Ego's mass in Thor Vol. 1 #202–203, and the sample grew into a second planet-sized intelligence that called itself Ego-Prime and nearly destroyed Earth.

The other sibling — Ego has a second brother, Id the Selfish Moon, a smaller living moon from the Black Galaxy who abandoned Ego to go partying across the cosmos and met his end in Deadpool Vol. 1 #35 (2011).

Gallery

Three looks at a planet with a face: a 1974 splash page, John Byrne's version, and the panel that introduces him in a single sentence.

Splash page from Thor issue 227 showing Ego the Living Planet's huge face filling the page, with Thor tiny at his feet and lava erupting — **The face that fills a page**A splash page from Thor Vol. 1 #227 (1974): Ego's face occupies the entire frame and Thor stands as a speck at his feet, from the arc in which Thor journeys inside the living planet and learns what made him.

John Byrne comic panel of Ego the Living Planet's bearded face looming in space beside a small starship — **Byrne's Ego**John Byrne's Ego from Fantastic Four Vol. 1 #234 (1981): the living planet's bearded face looms over a starship so small it reads as a toy, which is exactly how Ego prefers his visitors.

Comic panel of Ego the Living Planet, a rocky world with a human face, looming over a smaller planet in space — **This is Ego**A panel that introduces him in one breath — a world with a face, a beard, and a grudge against anything smaller than itself, which in Ego's case is everything.

Sources

Every fact on this page was checked against at least two independent sources before publication.

Bullpen Bulletins

Wikipedia — Ego the Living Planet Ego's Thor #132 debut, the Egros origin, and the Stranger's experiment: brother Alter Ego held captive by the Collector, wounded in the brothers' fight, his fragments forming Ego's moon.
Marvel.com — Alter Ego Marvel's own character page: the Stranger created Alter Ego as a bargain to the Collector, and kept it imprisoned to learn whether freedom or captivity bred the stronger will.
Marvel Database — Astonishing Thor Vol. 1 #5 The "Planetfall" finale: Ego and Alter Ego tear into each other with Earth as collateral, and the Stranger concedes his experiment ended not in destruction but in a family.