South Island Adventure is a large scale hack of Sonic the Hedgehog by Hivebrain, featuring Espio the Chameleon. It has new sprites, several new levels, and numerous other alterations.
- South Island Zone: Palette and layout edit of Green Hill Zone.
- Indigo City Zone: Palette edit of Marble Zone.
- Aqua Lake Zone: Palette and tile edit of Labyrinth Zone, meant to resemble Aqua Lake Zone from the 8-bit version of Sonic 2.
- Winter Hill Zone: Palette and layout edit of Green Hill Zone, with the background from Labyrinth Zone.
- Celestial Zone: Palette edit of Star Light Zone.
- Eggmanland Zone: Based on tiles from Metallic Madness Zone in Sonic CD. This was the first time level tiles had been successfully ported from Sonic CD to another game.
An earlier version of South Island Adventure, which has been listed in GoodGen, is a relatively simple palette and graphics hack in which you play as Super Sonic.