Exetior

Exetior (also known as Sonic.exe) is the titular main antagonist of the Sonic.exe: Nightmare Version series, as well in SMK series. He serves as the overarching antagonist in Mario.exe series.
== History ==
Exetior, originally one of the Highests, was a cosmic entity responsible for creating life on Mobius. Initially, when Exetior erased Mobius, there was no emotional impact. However, with each subsequent erasure, Exetior developed a growing attachment to Mobius and its inhabitants, although he tried to conceal it. In an effort to halt the cycle of erasures, Exetior assumed the guise of a demon named Sharpness and descended to Mobius. His objective was to understand the inhabitants and assemble an army of demons. Along his journey, he formed a friendship with a demon named Negagen, who possessed the power of waves. However, Exetior's true identity was eventually exposed, leading to a war with the Highests. Fortunately, he received support from Sark, Pervision, and Negagen. Despite their assistance, Exetior was defeated in the war, stripped of his powers, and banished to Hell, where he transformed into a demon of sharpness. Four thousand years later, due to disturbances caused by the Master Emerald, Exetior managed to escape from his prison. Pursued by the guards of Hell, he made his way to Mobius, where he encountered Sonic the Hedgehog. To conceal his true form, Exetior assumed Sonic's appearance by copying it. Exetior attempted to possess Sonic, but his efforts were thwarted by Creep, who protected Sonic from possession. Creep informed Exetior that Sonic's strong will made it challenging to possess him. However, if the three main sources of Sonic's determination, namely Tails, Knuckles, and Eggman, were eliminated, Sonic would become vulnerable and susceptible to possession. Agreeing to this plan, Exetior temporarily took control of Sonic's body.
=== Death (Best Ending) ===
When Exetior failed to kill one of his victim, Sonic encounters Exetior. He angrily tells Exetior to stay away from them so nobody gets hurt. Ignoring Sonic's warning, Exetior spindashes Sonic when he sees the Master Emerald behind him.
== Appearance ==
Exetior resembles to Sonic, he has dark blue fur, his eyelids are seemigly torn off, he also has black eye with glowing red pupils similar to the original Sonic.exe.
== Personality ==
In "Sonic.exe: The Nightmare Beginning," Exetior is depicted as a merciless, malevolent, and exceedingly murderous demon. His primary objective is to acquire souls in order to enhance his own power, displaying a complete disregard for the well-being of the other inhabitants of Mobius, whom he derogatorily refers to as "Pathetic piece of meat." This particular portrayal of Exetior's personality is commonly referred to as "Old Exetior."
However, in "Sally.exe: Continued Nightmare - Eye of Three," despite his extreme homicidal tendencies, Exetior exhibits a surprising contrast in behavior. He demonstrates kindness, rationality, compassion, and remarkable intelligence when interacting with the other demons.
== Trivia ==
* Contrary to common belief, Exetior is not Sonic's alter-ego or an evil counterpart. Rather, he was once a elite highest who became a demon and took control of Sonic's body.