Sonic.exe looks exactly like the original Sonic the Hedgehog. The only two known differences are his teeth and eyes (most notably his eyes); his teeth are yellowish and extremely sharp with fangs, and his eyes are pitch black with red, glowing pupils. His eyes also bleed most of the time. In the "I AM GOD." screen, a very gruesome "hyper-realistic" closeup of Sonic.exe's face, there's blood and bits of flesh around his mouth, although strangely, no blood was dripping was from his eyes at all in the image.
The earliest known history of Sonic.exe is when the protagonist (Tom) gets a CD game for the computer from his friend Kyle. Kyle leaves a note telling him to destroy the CD, because someone (Sonic.exe) is chasing him, and he'll come after Tom too if he doesn't destroy the CD. Tom, being curious about the CD, decided to play it instead. He started off as Tails, only to be forced into a game of "Tag" with Sonic.exe, the villain protagonist of the game. Sonic.exe was able to chase down Tails in mere seconds and kill him. Tom then picked Knuckles, where he went through Scrap Brain Zone with a strange background. After a while, Knuckles encountered Sonic.exe, and tried to attack, only to be killed. Tom then played as Robotnik, although after making it through most of the level, a very disturbing image appears, showing a realistic closeup of Sonic.exe's bloody face staring right at Tom for approximately 30 seconds with the caption "I AM GOD." at the top. Then static appears, and Robotnik is killed by Sonic.exe off-screen. After that, the game ends, and Sonic.exe appears to Tom in real life, in plush form. What happened after is unknown, but Tom most likely ended up with Tails, Knuckles, Robotnik, and possibly Kyle.
Flying: When Sonic.exe started to chase Tails, he started flying in a position similar to Metal Sonic in Sonic the Hedgehog CD.
Teleportation: Sonic.exe, as revealed in his fight with Knuckles, can teleport to avoid attacks.
Instant Killing: In a span of at most 15 seconds, Sonic.exe can kill someone instantly. After the victim is killed, their appearance is drastically changed, normally giving them a darker, lifeless skin tone, bloodying them, and making them look sad and morbid in general.
- He does not have a super form.
- His laugh is the Kefka laugh from Final Fantasy III on the Super NES.
- Also, the laugh heard during the "I AM GOD." screen is the same as the Kefka laugh, except it has been heavily distorted to sound more demonic (keeping in touch with the Creepypasta).