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This article contains plot details.
The story takes place after Sonic Heroes, with Shadow suffering from amnesia. At the start of the game, aliens begin to invade the world and Shadow is approached by their leader, Black Doom. Black Dooms says that they had an old agreement in which Shadow would bring him the Chaos Emeralds. Seeing as Black Doom knows him, this compels Shadow to find the Chaos Emeralds in order to uncover his past.
Depending on which path Shadow takes, he will end up at one of ten endings. When all ten ending are gotten, the final story is unlocked. Completing the final story will unlock the true ending.
The pure dark level is GUN Fortress.
For the dark mission, Shadow must destroy GUN's three central computers. The bosses at the end are Sonic and Diablon. Shadow declares that he was created to bring order and justice to the humans and that he would destroy the planet.
For the hero mission, Shadow must help Rouge find the sixth Chaos Emerald. The boss at the end is Black Doom. After Black Doom is defeated, Shadow declares that he will conquer the universe.
The semi-dark level is Black Comet.
For the dark mission, Shadow must eliminate all of the GUN forces. The bosses at the end are Sonic and Diablon. Shadow steals the seventh Chaos Emerald from them and states that he is a protector and a servant for Black Doom.
For the hero mission, Shadow must get to the center of the Comet with Knuckles. Dr. Eggman appears and demands the six emeralds that Shadow has. After he is defeated, Shadow declares that only he knows what's best and that he's the master of his own life.
The neutral level is Lava Shelter.
For the dark mission, Shadow must activate Dr. Eggman's base defenses to stop GUN. Dr. Eggman then states that this Shadow is a copy of the original Shadow and that the original died. After Shadow defeats him, he declares that he is a stronger version of the original Shadow the Hedgehog. He then kills Dr. Eggman.
For the hero mission, Shadow must help E-123 Omega find Dr. Eggman and defeat his army. Before the boss battle, Shadow states that he will make Dr. Eggman regret creating him. Afterwards, he declares himself "Shadow Android" and plans to take over Dr. Eggman's empire. Once again, Dr. Eggman is killed.
The semi-hero level is Cosmic Fall.
For the dark mission, Shadow must find a Chaos Emerald. The boss battle is against Dr. Eggman. Shadow spares him and calls himself the protector of the ARK.
For the hero mission, Shadow must help Vector find the computer room before the ARK explodes. The boss battle is against Black Doom. At the end, Shadow accepts that he is an experiment gone horribly wrong.
The pure hero level is Final Haunt.
For the dark mission, Shadow must activate the Comet's shields. The boss fight is against Sonic and Diablon. Once he defeats them, Shadow declares that he is the most powerful hedgehog in the universe.
For the hero mission, Shadow must find Black Doom. After defeating him, he states that he intends to keep the promise he made to Maria and protect the planet.
After defeating Devil Doom, Super Shadow flies underneath the Black Comet and uses Chaos Control to transport it into the Eclipse Cannon's line of fire. The cannon goes off and the comet is destroyed. Aboard the ARK, Shadow looks at a picture of Maria and Gerald. Tossing it away, he says "Goodbye forever... Shadow the Hedgehog".
Shadow the Hedgehog received mixed to negative reviews. Common complaints were due to the game trying to hard to be mature and the inclusion of weapons. Critics also complained about the controls, such as the homing attack not working properly and the lack of manual aim for the guns.
However, the game was praised for its replay value. Notably, Nintendo Power gave the game an 8 out of 10.
- If you stay in the fight against Devil Doom long enough, Dr. Eggman will say that one of his robots rescued Shadow and that he wasn't an android.
- There are 326 possible story paths in the game.
- Super Hard Mode is unlocked after A-ranking every level and boss. This mode essentially acts as an epilogue.
- Jun Senoue, the game's lead musical composer, had two lyrical tracks, Broken by Sins of a Divine Mother, and Who I Am by Magna-Fi, in mind for the game. However, due to licensing issues, the songs had to be dropped.