Darkspine Sonic

Darkspine Sonic (ダークスパインソニック) is one of Sonic's super transformations, appearing in Sonic and the Secret Rings. Rather than Chaos Emeralds, he uses the power of the World Rings. He is playable in the final battle against Alf-Layla-wa-Layla, an enhanced form of Erazor Djinn.

In this form, Sonic has increased strength and the ability to fly, along with his ring powers Time Break and Speed Break. His attacks are also more close-combat based, as opposed to the boosting and energy moves that Super Sonic uses. He does not lose rings gradually like Super Sonic, but he can lose rings from being hit.

Appearance
His fur becomes blue\purple in color with two golden rings around his wrists and two around his ankles. His gloves and shoes disappear, too. Two white lines come down from the middle of his forehead and white markings outline where the straps of his shoes were. His skin turns pale white, and his irises, pupils and mouth disappear. Also, his voice has a slight change, becoming more demonic, but maintaining Sonic's pitch, possibly due to the negative ring energies that give a slightly evil side effect.

Trivia

 * This form seems to resemble Dark Sonic from Sonic X. Both are darker, more sinister forms provoked by negative emotions.
 * Sonic's body and clothing merges in on itself when he becomes Darkspine Sonic, which is why his feet resemble his shoes, his arms appear the same color as his body, the cuffs on his shoes and gloves become Rings and why his eyes appear as they are.
 * Darkspine Sonic is one of three forced Sonic transformations, the others being Sonic the Werehog and Excalibur Sonic.
 * Darkspine Sonic can be considered the second form of Sonic that was not attained using regular Chaos Emeralds and the first in-game transformation that uses negative energy.
 * Darkspine Sonic seems to be more popular than Excalibur Sonic, which is the form he takes in Sonic and the Black Knight.

Quotes
"If this is your world, then it's a world that I don't want any part of!"-Just before the boss fight.

"Your tale is finished, Erazor! Next time, try writing a better story!"-After the boss fight.

"''We've got to... stop him! Shahra...please! Lend me your... POWER!" -End of cutscene''