The Unified World is a location that appears in the Sonic the Hedgehog comic series and its spin-offs, and the Mega Man comic series, published by Archie Comics. It was a fusion of Sonic's World and Earth in the year 20XX, the creation of which was brought about by the Maverick Sigma in his attempt to drain them of its life force.
The world contains all of the locales of both Sonic's World and Earth in the year 20XX meshed together and overlapping. Since the world was created during the time Sonic's World was experiencing the Shattered World Crisis, the entire planet was split apart.
Seeking the power of further his evolution, Sigma orchestrated for Sonic's World and Earth in the year 20XX to be merged so he could route their planetary energies into him in one swell swoop. Using Sonic Man and M'egga Man, Sigma had them plant Unity Engines on the worlds, forcing them into merging into the Unified world. The process would cause environments from each world to overlap each other, costing many lives, while Sigma harvested the Unified World's energies with the Master Engine.
Due to Sigma's syphoning the Unified World's energies, the planet and its inhabitants began dying, nearly leaving the planet an empty husk. When Xander Payne prevented Sigma's plot from unfolding by changing the past though, the events that created the Unified World were erased, returning Sonic's World and Earth to normal.
- The Unified World is similar to the Skull Egg Zone, as both were the main setting of a Sonic and Mega Man crossover storyline and had design that borrowed from various Sonic and Mega Man locales.
- Sonic Universe #77, "Worlds Unite! Part Five: Everybody in the Same Boat"
- Mega Man #51, "Worlds Unite! Part Eight: Holes in Reality"
- Sonic the Hedgehog #273, "Worlds Unite Part Three: Clash of the Corrupted"
- Mega Man #50, "Worlds Unite Part Four: Death and Destruction"
- Mega Man #52, "Worlds Unite Part Twelve: Last Rights"