Sonic Chronicles The Dark Brotherhood is a role-playing video game developed by BioWare for the Nintendo DS. Set in the Sonic the Hedgehog universe, the narrative begins with the kidnapping of Knuckles and the loss of the Chaos Emeralds. Players control Sonic and his allies as they traverse two dimensions, team up with Shade the Echidna, and confront Ix, leader of the Nocturnus tribe, to thwart the impending invasion.
The game initially focuses on the events surrounding the kidnapping of Knuckles and the disappearance of the Chaos Emeralds after the defeat of Doctor Eggman, before moving on to follow the cast of characters across two dimensions as they encounter a new ally, Shade the Echidna, and seek to stop the invasion of their world by Ix, the leader of Shade's tribe, the Nocturnus.