Battleworld was a pieced together planet from other planets made by the Beyonder for a group of selected heroes and villains to fight in during the Secret Wars event.
After seeing the people of Earth, the Beyonder viewed himself as incomplete, and to satisfy his new found emotion and questioning of the concept of desire, something he thought was the driving force of all living beings, he decided to perform an experiment to understand the concept and difference from good, evil and desire.
Beyonder then took many well known heroes from Earth, this included members of the Avengers, X-Men, Fantastic Four, and solo heroes such as She-Hulk and Spider-Man and put them on a makeshift planet the Beyonder made by taking parts from other planets and putting them together into one planet, called Battleworld.
The heroes and villains fought on Battleworld as a part of the Beyonder's experiment to see which was better, good or evil, along with the prize the Beyonder promised.
Long after many heroes and villains left Battleworld, and the Secret Wars were over, the planet of Battleworld went into an odd state where any wish would be granted to those who asked. Captain America asked for his original shield to be repaired, and Ben Grimm asked for the ability to transform to his Thing form, and switch back to his human form whenever he pleased.
Shortly after Ben Grimm left Battleworld, it exploded. It has not been seen since.
Battleworld is pieced together from other planets. It has a wide variety of terrain and wildlife, as well as many living races that called it home. It used to orbit a star.
- In episode 61 of the Spider-Man (1994 TV series) an episode called "Arrival" aired where the plot was that Spider-Man, The Fantastic Four, Captain America, Storm, Black Cat and others were teleported to a planet by the Beyonder, which was Battleworld.
- Several characters that were in the original Secret Wars comic book series were not included due to voice acting issues.