Exeniac is seen at the beginning with Exetior, who tells him that team "ZT-12" decided to betray him and take the "Chaos Crown" for themselves, and says that he thinks Exeniac can deal with the problem. Exeniac confirms that he can handle it, but tells Exetior to not forget his part of the deal, as since Exeniac decided to help him, Exetior "owes" him.
Exetior looks surprised for a second, before telling him to not waste time, as the task will not fulfill itself. Exeniac then goes on his way. He is also later seen imitated by Exetior, who says "We're stronger than you!"
Exeniac is shown to be arrogant, as he brags about his strength. He immediately sees helping Exetior as him owing Exeniac something.
Exeniac looks similar to Sonic, but his fur is a slightly greenish shade of blue, and his eyes have black sclerae with red pupils and blood coming out of them, messier quills, bloodied gloves, and a cut on his stomach.