Sonic Unlimited v3.0 and v3.5 are likely versions of a fan-made game or ROM hack. These versions likely indicate incremental updates and improvements over time, suggesting continuous development and refinement by the creator(s). As fan-made works, they would probably retain the essence of the original Sonic gameplay but add new features, levels, or story elements. Sega, the original creator of Sonic, would not be involved in these versions.  These games are examples of how fan communities extend the life and creative potential of classic gaming titles.

Sonic Unlimited v3.0

Sonic The Movie 3