In this universe, Chaos Emerald radiation transformed Sonic into a hideous, gigantic monster. Somehow half a Chaos Emerald became embedded in his chest like his father, Jules-Zilla. After an anguished Sonic the Hedgehog in Giant Robotno accidentally killed Jules-Zilla and left with his Emerald half, Sonic-Zilla emerged and cried at his dead father's body. Sonic-Zilla along with Espio-Zilla, Mighty-Zilla, Vector-Zilla are the only ones not to fight Giant Robotno despite Sonic-Zilla being present on Knothole Island. (SSS: #12)
- Sonic-Zilla is an obvious parody of the Toho monster Godzilla.
- Sonic-Zilla is the only mutated Mobian from Knothole Island without sharp fangs (not including Chuck-Zilla).