Darkspine Sonic is a transformation that appears in Sonic and the Secret Rings. It is a transformation of Sonic the Hedgehog's, achieved when he unwillingly used the World Rings of rage, hatred and sadness when they left Alf Layla wa-Layla and merge with Sonic, on their own. In this form, Sonic is slightly more violent and aggressive due to the influence of the World Rings' sealed feelings. He is only playable in the final battle against Alf Layla wa-Layla, an enhanced form of Erazor Djinn.
In this form, Sonic's fur and arms become a deep indigo color, and his skin turns pale white. He also gains a single, thick white stripe around his feet, and around his arms (close to where his elbows are), as well as a pair of much thinner white stripes that go up his forehead and down his upper middle quill, and a secondary pair of stripes on his lower middle quill. In addition, Sonic's pupils and irises disappear entirely (along with his mouth), while his eyes become slightly more angular in shape, and his quills hang lower than usual. In terms of attire, Sonic loses his trademark gloves and shoes and instead gains four glowing golden rings around his wrists and ankles. His voice also undergoes a slight change: becoming much gruffer, but maintaining its normal pitch. He is also constantly enveloped by a large flaming orange aura.
Powers and Abilities
In this form, Sonic has increased physical strength, enough to send Alf Layla wa-Layla's strongest attack back at him with brute force alone. He also obtains the power of high-speed flight, similar to his Super State. He is also granted pyrokinetic abilities, allowing him to create and control fire (though it is not shown to what extent). In combat, he can create concentrated flames on his hands and feet to amplify the destructive force behind his attacks, and form highly powerful bursts of flames. His attacks focus more on hand-to-hand combat, as opposed to the boosting and energy moves that Super Sonic uses. He is also able to perform Time Break and Speed Break without relying on the magic of Shahra's Ring, and he can generate the necessary amount of soul energy he needs for these moves, himself.
As the World Rings are what keep the world of the Arabian Nights together, it appears that Darkspine Sonic is also capable of warping the reality of the Arabian Nights' universe: with one gesture, Sonic was able to revert Erazor Djinn's realm back to normal while also expelling the World Rings' power from his body.