The series was announced under the title Cosmic Champions in the eleventh issue of the Marvel Age news magazine, cover dated February 1984.

Mattel's involvement influenced the storyline and character design, including making Doctor Doom and Iron Man's armor more high-tech to appeal to kids.

"[13] The heroes include the Avengers (Captain America, Captain Marvel, Hawkeye, Iron Man, She-Hulk, Thor, the Wasp, and the Hulk), three members of the Fantastic Four (Human Torch, Mister Fantastic and the Thing), solo heroes (Spider-Man and Spider-Woman) and the mutant team the X-Men (Colossus, Cyclops, Nightcrawler, Professor X, Rogue, Storm, Wolverine, and Lockheed the Dragon).

Ultron is drained of energy by Galactus, who then tries to confront the Beyonder while Doctor Doom observes, but both are easily defeated and sent crashing down to Battleworld.

The heroes win the first skirmish, causing the villains to fall back, only to be assaulted by Ultron, having been rebuilt by Doctor Doom.

Doom creates villainesses Titania and Volcana,[14] then leads the remaining villains in a successful assault on the heroes and their base, which they bury under a mountain.

Doom's faction returns and attacks the heroes, while he sneaks onto Galactus' ship and persuades Klaw to join the villains.

[16] Molecule Man brings the villains to Volcana's apartment on Battleworld then takes the suburb of Denver back to Earth.

However, the Thing, having gained the ability to revert to his original human form of Ben Grimm at will, chooses to remain on Battleworld for a year to explore the galaxy.

An announcement of a sequel series, Secret Wars II, from Carol Kalish, Marvel's Direct Sales Manager at the time, was first met with boos.

Zalben praised Secret Wars' story and lasting effect on the Marvel universe, as well as honoring the storyline as the "semi-official first Event Comics ever.

The Beyonder merged dozens of fragments from many planets (including a suburb of Denver, Colorado, from Earth), to create Battleworld, intended to provide an unfamiliar environment where all contestants could use their powers to the fullest.

[25] In the aftermath of Secret Wars, the planet became infected with cosmic energy when the Beyonder reclaimed his stolen power from Doctor Doom.

This led to a "wish fulfillment" phenomenon whereby force of will could alter reality; for example, repairing Captain America's unbreakable shield or allowing Mister Fantastic to create a way to take them quickly home.

He stayed behind because he was able to change to and from his human form while on the planet's surface; his adventures were recounted in his own side-series while She-Hulk took his place in the Fantastic Four.

[28] After Ben returned home—he had defeated Ultron and slain his manifested dark side Grimm the Sorcerer—the planet had no more reason to exist and broke apart.

[29] It is unknown whether all pieces returned to their home planets; the fragment of Colorado was ferried back to Earth with its citizens and the Secret Wars' villains by Molecule Man.

This faux Battleworld was destroyed at the end of the miniseries by the departure of the irate Stranger with Gravity holding it together long enough for his group to escape at the cost of his life.

Doctor Doom used a secret weapon made up of a multitudinous number of Molecule Men to defeat these Beyonders and usurp their omnipotence for himself.

[27] Afterwards, he salvaged the remaining realities and merged them into Battleworld, made in his own image and filled with mindwiped residents who worshipped him as God Emperor.

[31] Battleworld is orbited by a small Sun, in fact the Human Torch, consigned to the role for acting against Doctor Doom.

When the Elders of the Universe of the restored Earth-616 realized that the Multiverse had endured a death and a rebirth, the Collector and Grandmaster discovered the remnants of Battleworld and resolved to fight for the possession of the Iso-8 and used the broken shell as the arena (known as Battlerealm) for their Contest of Champions, a competition where several individuals, taken from Battleworld and the reborn Multiverse, fought to the death on behalf of each Elder.

Written by Dwayne McDuffie and illustrated by Scott Kolins, it referred back to the original Secret Wars event with a similar premise as the Beyonder again transported superheroes and supervillains of Earth to fight on Battleworld.

It was released in conjunction with Avengers & The Infinity Gauntlet and Captain America & The Korvac Saga, similar self-contained, all-ages re-imaginations of past events, that appear to take place in their own separate continuities in the standard "Marvel Adventures" manner.

It retold the events of the original miniseries from Deadpool's point of view and used retroactive continuity to fix inconsistencies with later stories.

A four-issue miniseries titled Marvel Super Heroes Secret Wars: Battleworld was released in conjunction with the 40th anniversary of the original series, beginning in November 2023.

[51] In Spider-Man: Life Story, which depicts an alternate version of the Marvel Universe (designated Earth-19529) where characters aged in real time and debuted in the same year as their first issue publications, the Secret Wars began in 1984 when a number of United States-based superheroes were transported to Battleworld by the Beyonder.