Original, Fake. Hero, Dark. Truth, Lie. Older, Younger. The Chaos Emeralds have brought the twins to a world much different than their own. Hub is a Shadow of his old self and Lan's going at Sonic speeds. And as we all know, Shadow and Sonic, are destined to clash.
At the end of the epic 'Worlds Unite' saga, Sticks the Badger Hinted at some sort of 'Nexus' world. One where the stories of a Blue Blur and a Blue Bomber were combined perhaps? Meet planet Nexus' Freedom Fighters! Sonic, the speedy hedgehog who loves freedom, and Rock, AKA Mega Man, who has a sense of justice few could hope to have. Don't forget their friends! And, their enemies..
A botched scheme of an evil genius has prompted Sonic to go on an adventure, and it's not Dr. Wily! Dr. Eggman, in league with a creature called 'Chaos', is wreaking havoc on the misplaced Station Square. The race is on for the Chaos Emeralds, and Sonic is determined to stay in the lead. Heroes new and old enter the race, will they win before the countdown to Chaos runs out?