|This character exists primarily or exclusively within the Pre-Super Genesis Wave continuity.|
Information in this article may not be canonical to the storyline of the games or any other Sonic continuity.
In addition to being composed of nanomachines that were able to morph and adapt after each defeat, Dr. Robotnik outfitted E.V.E. with a DNA sample taken from Sonic himself (a quill taken from the hedgehog's hide), as well as organic material from Robotnik's own brain. These separate DNA patterns were meant to give E.V.E. Robotnik's genius in combination with Sonic's ingenuity. E.V.E.'s original form is that of a state-of-the-art, jet-pack-wearing SWATbot, but upon being scrapped by Sonic, it transforms into something suitable to counter Sonic's speed: a giant hornet. Thinking he is being attacked by separate robots, Sonic destroys E.V.E. twice, only for her to revert to a metallic ooze and reshape into a more lethal form.
After wrecking E.V.E.'s second (hornet) form, Sonic goes to confront Robotnik, who gloats that E.V.E. can never be defeated and will only learn from each victory. E.V.E. then bursts into Robotnik's headquarters and attacks Sonic in the form of a giant cobra, which he defeats. Her response is to take the form of a tentacled entity with two large eyes, an enormous mouth, and a crystal-like brain, after which she turns the tables by turning on her creator. Although Robotnik tries to re-assert control, E.V.E. reveals that by adding Sonic's DNA to her systems, Robotnik mistakenly implanted a streak of independence instead of the resourcefulness that he'd intended her to receive. Instead of developing his intelligence, all she got from Robotnik was his evil, which was negated by the inherent good she inherited from Sonic. E.V.E. seemingly vaporizes her master-but in reality only sent him to a parallel future and an encounter with a defeated version of himself-and turns her attention to Sonic, intending to fulfill her programming. Thinking quick, Sonic reasons to E.V.E. that she will never be free if she continues following orders. Upon realizing her own free will, E.V.E. thanks Sonic and soars into outer space, her brain-like form growing larger so that the tentacles are replaced by butterfly wings made of pure energy.
Sonic encounters E.V.E. again after he is stranded in deep space and trying to get back to Mobius. The increasingly-powerful E.V.E. had been seeking out planets whose natives employed computers to work for them. This E.V.E. shared the outward appearance of her previous incarnation, though in much larger form. Inside, however, the main unit was anthropomorphic, and feminine in appearance. Feeling the need to "liberate" the machines, E.V.E. stripped these worlds of all their minerals until they were reduced to lifeless rock, then integrated the computers into her own systems to evolve into a "higher organism". Outraged, Sonic points out to her that instead of serving their masters, these computers just obey E.V.E. instead. Hearing Sonic's words, E.V.E. determines that she is no better than the oppressor, that her mission is flawed, and must be terminated. After giving Sonic coordinates to help him get home, E.V.E. resets her course to the nearest star. During A.D.A.M.'s "gathering", it is revealed that this star was powered by yellow Chaos Emeralds.
E.V.E. has sub-microscopic components, brain cells from Dr. Robotnik and body cells from Sonic. She can transform into new machines, and can learn and adapt from past experiences.
- Dr. Robotnik said E.V.E. had an infinite amount of phases to defeat Sonic, however, when she was in her fourth phase, Robotnik stated that it was her final phase.