This page focuses on the last story of Sonic Adventure: Chaos Unleashed after clearing all 6 stories.
Here are the links to the other six stories:
- Main article: Sonic Adventure: Chaos Unleashed/Sonic's Story
- Main article: Sonic Adventure: Chaos Unleashed/Tails' Story
- Main article: Sonic Adventure: Chaos Unleashed/Knuckles' Story
- Main article: Sonic Adventure: Chaos Unleashed/Amy's Story
- Main article: Sonic Adventure: Chaos Unleashed/Big's Story
- Main article: Sonic Adventure: Chaos Unleashed/Gamma's Story
Super Sonic Story
We are taken to a scene at Big's hut in which the Tornado is on the ground with the last Emerald. Meanwhile, Eggman is flying on his Eggmobile muttering to Orbot and Cubot about his hatred of Sonic, knowing that he cannot spoil his master plan. Just then, the villainous trio spot Chaos lurking around. Eggman gasped in relief that the monster has survived, and tells him they can find the Chaos Emeralds again, but this turns into horror as the beast attacks him, Orbot, and Cubot.
Meanwhile, Knuckles is noticing that Angel Island is falling again; he suspects that the six Chaos Emeralds he brought with him over his last story was the cause of it and decides to take them to Sonic. He later spots Eggman, Orbot, and Cubot lying on the ground. Before Eggman could explain, Chaos appears and attacks Knuckles, stealing the Chaos Emeralds.
Somewhere else at the Mystic Ruins, Sonic is relaxing by a tree when Tails informs him that Angel Island has fallen. So the two hurry to Angel Island.
Adventure Field: Mystic Ruins
When Sonic and Tails arrive to the shrine, they spot Knuckles, Eggman, Orbot, and Cubot on the ground. Knuckles tells Sonic and Tails that Chaos has survived and has stolen the 6 Chaos Emeralds. Eggman grabs Orbot and Cubot and heads off on his Eggmobile to his base to conspire a plan to deal with Chaos. Knuckles tells Sonic about Chaos' ferocity and states that if he gets the last Chaos Emerald, death will come. Sonic knows that he'll find it before the monster does, but a light appears and he and Knuckles are sent to 4,000 years to the past.
Adventure Field: Mystic Ruins (The Past)
Sonic and Knuckles appear to the altar and sees a group of echidnas - the Knuckles Clan - heading to it. Tikal tries to reason with them, but Pachacamac ignores her and orders his soldiers to charge, knocking down Tikal to the ground and injures many Chao. As a result, Chaos appears and is enraged. The echidna clan were shocked and Chaos absorbs the Chaos Emeralds and kills the warring echidnas. He then continues his path of destruction to another location.
Sonic and Knuckles head over to Tikal to see if she's okay. Tikal realizes Chaos is wreaking havoc and seals him and herself within the Master Emerald for all eternity before he could destroy the rest of the world.
Sonic and Knuckles return to the present day where Tails was waiting. Realizing the significance of the three dreams he had in his story, Knuckles explains to Sonic and Tails about what the dream meant - Chaos had used the 7 Emeralds before and destroyed most of the echidna civilization. Tails says that they have to get the last emerald from the Tornado 2 before Chaos does.
Adventure Field: Mystic Ruins
The three head over to Big's hut and spot the Tornado 2. Just when they are about to get the emerald, Chaos arrives, devours destroying the Tornado 2 and absorbs the Emerald. Now the heroes' hopes are dashed.
Chaos, now Perfect Chaos, goes on a rampage in Station Square, flooding the entire city. Roads, highways, and buildings were all damaged. There is a cutscene where the news reporters inform of the devastation; they say that many citizens of Station Square were evacuated safely, but a few others have drowned and are in the process of being rescued.
Sonic arrives to the destroyed Station Square, now realizing how vicious Chaos really is. He then spots the Egg Carrier 2 from the corner of his left eye and knows that Eggman is after the monster. Eggman attempts to engage in combat, seeking to destroy Chaos for disobedience, but Chaos demolishes the fortress to ruin with a massive beam of energy. Sonic is getting aggravated with Chaos' ferocity, but Tikal arrives. Sonic realizes Tikal sealed Chaos in the Master Emerald. She states that her heart's been always with the Master Emerald as well as Chaos', but he's full of anger and sadness. If this isn't stopped, he will bring destruction to the Earth like he did centuries ago. Chaos then discards the Chaos Emeralds, which are now powerless and dim in color; one of them lands in front of Sonic and Tikal. Shocked about this, Tikal demands that Chaos must be resealed in the Master Emerald, but Sonic doesn't think this will help. He tells her that sealing Chaos back won't change how he feels from within. His heart will still remain in turmoil and his anger won't vanish; he'll just be trapped forever, and history will just repeat itself as it did before. Instead, Sonic opts for another solution: destroying the anger and rage within Chaos' heart.
Tails, Knuckles, Amy, Cream, Vanilla, Big each bring the other 6 Chaos Emeralds and Tails informs Sonic that Chaos has absorbed the Emeralds' negative power, and that Sonic should be able to harness their positive power. Closing his eyes and using the positive energy of his friends and the citizens of Station Square, Sonic restores the Chaos Emeralds to their normal state and transforms into Super Sonic. He then flies off to engage the gargantuan war god in battle.
Final Boss: Perfect Chaos (Phase 1 and 2)
After a grueling battle, Chaos is reverted to his normal form, Chaos 0; his anger and rage has finally faded. He spots several of his organic kind, the Chao, and knows of their peacefulness; even Cheese, Cream's Chao comes up to him. Tikal arrives and tells Chaos that the Chao have been living peacefully with mankind for a long time and continue to do so. With the fighting over and harmony restored, the circle of life moves on. She thanks Sonic and the others for their help she and Chaos then return to their time.
Seconds after, Eggman, Orbot, and Cubot fly away in the Eggmobile. Cubot asks him why is he leaving a now destroyed Station Square, knowing that he can build Eggmanland on its ruins. Eggman explains that he can't build it when the ruins is flooded and decides that he will devise another plan to take over the world. Orbot gives a snarky remark about how his next scheme will result in the same result similar to Chaos, earning himself an angry smack on the head by Eggman.
The story ends as Sonic watches Eggman and his minions leave and decides to go after them in search for more adventures.