METAL SONIC AND THE DIGITAL ODYSSEY (Metal Sonic X SMG4)
8 parts Ongoing Mature(Disclaimer: This story is rated 18 and up, in the use of drugs, strong language, a massive amount of violence, blood, and possible sex scenes. I do not own Sonic and any of the SMG4 characters. They belong to SEGA, SMG4 himself, Nintendo, and Glitch Productions.)
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During the day that Sonic was crowned as king, Eggman attacked Mobotropolis with a full on invasion to take down the Freedom Fighters. Eggman planed to use the Phantom Ruby to banish Sonic and his friends to another dimension, making sure they stay there and never return.
After a long fight with Metal Sonic, as both he and Metal became super, Sonic was defeated but Eggman pulled the Chaos Emeralds from Sonic and Metal Sonic before the robot hedgehog could deliver the final blow. Eggman disowned Metal and called him useless before firing the cannon.
But Metal chose to take the Chaos Emeralds when the portal became unstable and turned into a black hole. While grabbing the Ruby, Metal Sonic sacrificed himself to save the world, making everyone believe him to be gone...
However, they did not know that he was sent to an alternate dimension, where he would begin his new life becoming a hero in the SMG4 universe, proving he will be a better hero than Sonic.