Just found this recently but for those such as myself who are curious, Sonic Dimensions is a PC Fan game created by Phantom-Radea. This game Plays similar to how Sonic Vs Darkeness, a fan game created by Nefaut1st plays in terms of it's mechanics and play style, but unlike sonic vs darkness which runs on the sol engine, it is stated that Sonic Dimensions runs on a modified version of the super ring engine, Essentially giving the game qualities and effects similar to how the sol engine works. Sonic Dimensions offers a variety of choices ranging from a basic adventure mode to doing time attacks, complete with a achievement system depending on certain tasks within the game. this game has two playable characters choosing from either sonic or shadow with abilities that slightly differ from each other so depending on who you choose will effect the overall play style. This game also offers the use of being able to use an Xbox360 controller to give it a more authentic feel to it. none much else to say really so if you want to try this, you can get it from here.
http://www.mediafire.com/download/5t51xx0stt9s6fa/Sonic+Dimensions.rar

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