- "Heh Heh. You want to know who I am? Me? Why I'm so twisted? ...When me and Shadow fused during that "Battle" with Darkstone Prime, Shadow would never let me control his body. He only did it once, so I could save him. I regret it. I have lived inside of him for many, many years now. I have seen people die. I have seen people be born. The only things surrounding me are a black void and a large window, being his eyes. All I felt was sadness and loneliness, being isolated in that dark void for so long... I was slowly turning grey and more sad, as more people forgot about me. Now that Shadow is dead, I am free... You think there is still some "Sonic" left in me? No. Not anymore. He died long ago. There is nothing left of the old me. I am no longer Sonic... from now on, I am Greyspeed!"
- —Greyspeed's answer when Tails asks him who he is and why is he twisted
Yet again, this takes place in ANOTHER alternate universe. This time, Sonic DID fuse with Shadow during a final battle, and everything that Greyspeed said is true in this universe. For more information, go here for his origin story. You can also use Greyspeed in your own fanfic if you would like to, as long as you give me credit and make a link to this page. Also, when using Greyspeed in a fanfic, DO NOT SHIP HIM. Not only does it make him cry, If you do so, I will OBLITERATE the page and/or article. If it is a picture, I will delete it off of the page. Understand?
Greyspeed is the physical form of Sonic's depression and anger. When Shadow and Sonic fused, they became Shadic. But this time, Shadow would not let Sonic take control of his body, thus causing Sonic to be in isolation (Trapped in Shadow's mind). This caused his anger and depression to get the best of him, and as everyone slowly forgot about him, he turned grey and greyer. Eventually, when Shadow died by falling off of a cliff, Greyspeed was released from Shadow's mind. Because he was just the physical form of anger, he went on a rampage, destroying Mobius. Sonic was dead, and his anger and depression took over his body. After possessing Tails and turning him into Blackflight, he then possessed Shadow's body and became a Darkstone Prime clone, which then the real Darkstone Prime comes through a time-warp. He then reveals that he is cloning himself over and over again by using a time-loop so he can build an army and take over the world. Then, after he successfully does this, he takes over the world, and eventually gets Mephiles and Infinite to be his Generals 1 and 2. After 3 years, Knuckles, Vector, Charmy, and Espio finally fight Darkstone Prime for real. But before the fight starts, Darkstone Prime uses a powerful move to knock out everyone but Knuckles. They then duel and eventually, Knuckles starts crying, knowing he is attacking his best friend. Then the ghost of Shadow comes, and apologizes and tells Sonic to come with him. This breaks Sonic out of his rage, making him turn back into Sonic and eject himself from Shadows dead body. Sonic then cries for a few minutes, and then uses a huge lightning attack to kill himself. The universe then becomes unstable, as Knuckles destroys the Emerald of Life, and the entire timeline resets, but this time, without Greyspeed.
He looks just like Sonic, only his eyes are just pitch black with no pupils representing his anger, and he is dark grey, representing his sadness. His shoes and gloves are the only normal things.
He is a bit transparent due to slowly fading away as he is being forgotten.
Unless his transformation into Darkstone counts, then no. He cannot go super, and he cannot go hyper.
Main Theme: https://www.youtube.com/watch?v=r_125V1bxoc - I am Porky - MOTHER 3
Battle Theme: https://www.youtube.com/watch?v=1z3at22wENo - Infinite Battle 1 - Sonic Forces
Final Battle: https://www.youtube.com/watch?v=nENrxSRqz78 - Battle Against the Masked Man - MOTHER 3
None as of now.