Sonic Chronicles: The Dark Brotherhood - Plot

Plot

The story of Sonic Chronicles is split into two acts, which are further divided into several chapters. The first takes place in Sonic's world, with the team attempting to unravel the situation they are in, while also stopping the Master Emerald from being taken. The second act sees Sonic and the team travelling to another dimension, called the Twilight Cage, in order to stop a new threat to their own world.

Sonic Chronicles opens by detailing Eggman's defeat, and presumed death, some time ago after the destruction of the Egg Carrier at the hands of Sonic and friends. In the present, Sonic is on vacation when he receives a call from Tails, stating that Knuckles has been kidnapped by a group called the Marauders, and have stolen the Chaos Emeralds. Travelling with Amy to meet Tails, they are escorted by Rouge the Bat to meet the GUN Commander, who informs them that they have been watching the Marauders for some time, and know where to search. Having no luck, they eventually locate the Marauders' base in the Mystic Ruins and with the help of Big the Cat, they find Knuckles, who is found escaping from some robots; leaving the base, they find Angel Island has gone. Devices found in their initial search help them locate Eggman, who claims to be a reformed character, revealing that he survived the crash of the Egg Carrier by anticipating his own defeat and making a robot that would rescue him. He informs the team that Angel Island is being pulled to Metropolis, the location of the Marauders' main base.

With Metropolis as their next destination, they meet Shadow and he joins up in order to find E-123 Omega, but are attacked by Shade and her Marauders. She reveals herself to be an Echidna of the Nocturnus Tribe, leaving Knuckles, supposedly the last of the Echidnas, shocked. After her defeat, the team head to Angel Island to get the Master Emerald before the Marauders, but are shot down; they confront the Nocturnus leader, the Grand Imperator Ix, who reveals his plot to take over the dimension. Shade is shocked, having believed that Ix merely wanted to bring her clan back to Earth, as they had been sealed in an alternate dimension called the Twilight Cage. Tails and Eggman arrive with a non-lethal weapon, using it transport several of the Nocturnus back to the Twilight Cage, but Ix escapes and steals the Master Emerald. This causes Angel Island to fall from the sky, and Knuckles saves Shade as the island crashes into Metropolis.

Tails and Eggman build a vehicle, dubbed the Cyclone, that will transport them to the other dimension, but Eggman claims he must remain to ensure their safe return; as they leave, he reveals that he has a more sinister plan in mind for them. Once in the Twilight Cage, the team encounter the rock-like Kron Colony, who assist them on their journey by providing them with a Chaos Emerald. Next, they meet the N'rrgal Colony, who will give the team their Chaos Emerald if they take a weapon from their enemies, the Zoah. Having gained the Zoah's weapon by defeating their leader in combat, the team discover it is another Chaos Emerald — the two races realise they have been duped by Ix, who gave them the Emeralds to keep each other in check. Two further Emeralds are found in the Voxai Colonies, inhabited by a telepathic race who have been controlled by a group of three Voxai known as the Overmind, whose dominating telepathic power stemmed from the use of Chaos Emeralds. The team defeat them, and the new leader gives them the two Emeralds that had been given to them by Ix.

With the remaining two Emeralds on Nocturne, the team gathers the leaders of all encountered colonies and carry out a plan to invade the Nocturnus home world. The Voxai find weaknesses in the force field around the planet, the Zoah fly a spaceship created by the Kron towards it and launch a missile which deploys a small group of N'rrgal to eat a hole in the force field. Splitting into two teams, they defeat two Gizoids (Scylla and Charyb) who each use a Chaos Emerald to wield the elements of fire and water, and also lower the force field surrounding Nocturne in order to allow the invading forces from the other Twilight Cage races to attack. Both Knuckles and Sonic's team then fights Ix, and are victorious; Ix then uses the Master Emerald to achieve a very powerful Transformation, but Sonic uses the Chaos Emeralds to become Super Sonic, and defeats him. As Nocturne begins to fall, and is nearly destroyed, the team escapes to the Cyclone and heads back to Earth. However, once they've arrived back in Metropolis, they find Eggman waiting for them with a fully rebuilt Metropolis, and the team take the Cyclone to confront the new Eggman Empire. The game ends at this cliffhanger moment as Eggman fires lasers at the Cyclone, shooting it down from the sky. Sonic, Tails, and Omega then break the fourth wall by citing the credits themselves.