Scourge the Hedgehog

Scourge the Hedgehog (Skōrugū za Hejjihoggu), also known as Evil Sonic, is an exact opposite of Sonic the Hedgehog, thus, he has all the same traits of Sonic, but he's evil. Scourge has green skin, a leather jacket, black-rimmed sun glasses, and black boots. Originally Scourge had blue skin like Sonic, but in an incident where he tried to drain power from the Master Emerald he changed in color.

Original Scourge
Evil Sonic hails from Anti-Mobius, a polar opposite of Sonic's world. There, he was leader of a group of thugs called the Anti-Freedom Fighters. Their arch-nemesis is Dr. Julian Kintobor, a nice scientist. Eventually, Evil Sonic was kicked out of the group and lined up behind someone even worse. Eventually, he ran into Julian's opposite: Dr. Ivo Robotnik. The two made a pact that Evil Sonic would impersonate Sonic; all he needed to do was change his attire to Sonic's. Another of their enemies is Anti Knuckles, a pacifistic alter ego of Knuckles the Echidna. Evil Sonic had tricked Anti-Knuckles into going to Mobius-Prime to give him some information there. Evil Sonic has crossed paths with Sonic-Prime many times, usually impersonating him and getting him into trouble, leaving the "real" Sonic to clean up the mess.

Custody and Escape
Evil Sonic was recruited by Robo Robotnik to help him with a plan, mainly to retrieve the Giant Borg, Robo's greatest invention. However, because of all these Robotniks, he accedently gave it to Dr. Robotnik from Sonic Underground. To show his gratitude, he imprisoned Evil Sonic and prepared him for Roboticization. However, being ignorant of who he was Manic and Sonia bailed him out. Then Manic, Sonia, and the Sonic from their universe, defeated Robotnik and anihilated the Giant Borg. As for Evil Sonic (or Scourge), he got captured by another alter ego of Sonic, Zonic the Hedgehog. From there, he was thrown in prison by Zonic. However, Evil Sonic escaped twice; the first time he Ko'd Zonic and went to Mobius-Prime, where Antione D'Coolette defeated him in a battle, and the second time, he broke out and went to Anti-Mobius, where he met Antione "Patch" D'Coolette who wanted to fight Evil Sonic. Scourge beat him and concocted a penalty for both alter egos; switch their positions in their universe. Eventually, he did the same thing with himself, allowing him to make serious moves on Amy Rose, Bunnie Rabbot, and Fiona Fox. Sonic however, quickly escaped the Anti-Verse via Julian Kintobor's help and arrived back to battle Evil Sonic in the Chaos Chamber, but were evenly matched again. Because of this, Lock the Echidna, Knuckles' father, used Chaos control to teleport him back to Anti-Mobius.

Neo Scourge
When he came back to Mobius-Prime again, he parnered up with Rouge the Bat to steal the Master Emerald. They, unbeknownst to each other, had seperate plans to do so; one would distract Lock while the other would take the Emerald, but neither knew who would distract and who would steal. This led to their plan being thwarted by Lock and Knuckles. However, Evil Sonic managed to touch the Emerald, and it mutated him; instead of blue skin and green eyes, he had green skin and blue eyes. And Rouge said to him, "I like the green bod, Evil Sonic." He said, "Yeah, baby, but I'm still the same old guy. I'm still Scourge the Hedgehog!" She was one of three people who Evil Sonic told his real name; the other two being: Sonic-Prime and Fiona Fox. Now that he had told Rouge his actual name, they went to attack Lock and Knuckles. After Knuckles got knocked out, Lock tackled Scourge and ripped his chest badly, which was how he got those jagged scars on his chest. Screaming in pain and bleeding badly, Scourge beat Lock horribly, stopping short of killing him when Rouge said she doesn't work with murderers (only to find that Lock's wounds killed him later). Then Scourge used the Master Emerald to intiate Chaos Control to teleport to Sonic. After a grueling battle on Sonic's part, and then being pursued by new enemy Shadow the Hedgehog, he and Rouge were teleported via Chaos Control by the evil Dark Legion leader, Dr. Finetivus. He convinced them to join up with him, only for Rouge to abandon Scourge after betraying the Doctor. Then Evil Sonic and Sleuth Dogg arrived to fight Sonic. Their mission was to obtain a Warp Ring that Rouge had taken. In an attempt to ransom the Ring, the two kidnapped Miles "Tails" Prower and Fiona Fox and would torture them to death if not given the Ring. Before leaving, Scourge told Fiona, Sonic's then girlfriend, that he wanted to see her again and he loved it when she pretendended that her and Sonic were for real. Some time later, he joined the Destructix group led by Mammoth Mogul and Ixis Naugus, and they attacked and destroyed a group of monsters on Angel Island, convincing the resurrected Lock that they had reformed. This enabled them to trick lock into gaining custody of Angel Island and the Master Emerald. Now they could carry out Dr. Finetivus' plan: to recreate Dimitri (AKA Enerjak) by giving him his body back and increasing his power a thousandfold. Then Scourge arrived in the city of Knothole, located on South Island, revealing that he and Fiona had been involved for quite some time. After a brief altercation with the Freedom Fighters, among them the disbeleiving Tails, Scourge and Fiona teleported with the Warp Ring, supposedly to talk to Scourge's bosses on Angel Island. By doing so, they escaped undergoing a sting operation, disguised as an auction of the Master Emerald, a trap that captured Fiona's old teammates Bark the Polar Bear, Fang the Sniper, Bean the Dynamite, Mammoth Mogul, and Ixis Naugus. Scourge arrives by himself to tell Dr. Finetivus, who apparently changed his mind on becoming Enerjak again.

Personality
Since he is an evil alternate version of Sonic, Evil Sonic has all of Sonic's traits, just darkened and at times, reversed. While Sonic enjoys the company of his friends, Scourge has none, and sees his allies as pawns to help him prove he's the best. In addition, where Sonic likes to battle just for sport, Evil Sonic fights to prove that he is the greatest by introducing his opponents to excrutiating pain, and if given the chance, kill them.