Worlds Unite is a comic book crossover storyline published by Archie Comics. A sequel to a previous crossover, Worlds Collide the story see's characters from Sega's Sonic the Hedgehog and Capcoms Mega Man franchise teaming up once again to save their worlds, this time also being joined by characters from other Sega and Capcom franchises, including NiGHTS and Reala.
The 12-part story arc ran across all of four of Archie's then-current video game based titles, specifically the Sonic the Hedgehogand Mega Man series, as well as Sonic's two spin-off titles Sonic Universe and Sonic Boom.
This marks the second time the NiGHTS universe has appeared in an Archie Comics series, after the 1996 miniseries, however their appearance here does not share a continuity with said series.
In the previous crossover, Sonic and Mega Man's worlds where hit by the reality warping Genesis Wave, which altered their two worlds. Mega Man was able to return his world to normal in the end, while Sonic's world was left perminantly altered into a different state than before. The "shards" of Sonic's old reality went on to tare holes in the fabric of the space time continuum, which manifested themselves across various realities as what would come to be known as "Genesis Portals", which allows individuals to traverse dimensions.
These portals and their capabilities were discovered by the evil Reploid virus Sigma, arch nemesis to Mega Man's distant-future successor, X. The evil A.I. utilised the portals in his plan to merge Sonic and Mega Man's planets together so that he could sap them both of their life force and become more powerful. Once the first phase was complete, Sigma sent his army of Maverick Reploids to seek out more worlds to draw power from.
Two of these Mavericks, Storm Eagle and Storm Owl, found their way to the Dream Gate, where they combated against NiGHTS and Reala. After working to keep the villains at bay, hell finally arrived in the form of Sonic's best buddy, Miles "Tails" Prower, and Mega Man's fellow Robot Master, Air Man, who aided in the final blow to the Reploids. With things settled down, the young two-tailed fox informed NiGHTS of Sigma's threat and asked that they assist them, to which NiGHTS happily accepted, and Reala, after being forced by Wiseman, reluctantly agreed to go along.
NiGHTS and Reala later joined the immense unified army of Sega and Capcom heroes in the final battle against Sigma and his forces, who was ultimately defeated by Sonic and Mega Man in their super forms. With reality too damaged to be reversed back their original states, however, all seemed lost anyway. That was until Xander Payne, a villain from Mega Man's world, used time travel to take Sigma out in the past, completely undoing this whole adventure. Like everybody involved in that battle, NiGHTS and Reala were likely returned to Nightopia with no recollection of their recent exploits.