The sequel improved the formula with more characters and better battle modes. It is the closest official experience to modern Sonic on the PSP. 3. Sonic Rivals: Unleashed (Fan Project)

: Any ISO files labeled as "Sonic Unleashed" for the PSP are likely:

While there were rumors that a PSP port was planned alongside the PS2 and Wii versions, it was reportedly due to technical limitations and Sega's focus on home consoles. Why You Might See "PSP ISO" Links Online

A 2D side-scrolling version for Java-based mobile phones and BlackBerry.

Because no official ISO exists, the "Sonic Unleashed PSP" experience usually refers to one of three things:

The shockwave shatters the planet into seven continents and drains the Chaos Emeralds, turning them gray and useless. A side effect of the dark energy transforms Sonic into a beastly at night. Eggman then ejects Sonic (and the Emeralds) back to the broken Earth. The Journey: Restoring the Light