Sonic 1: South Island Definitive

Sonic 1 Definitive is a hack named by RadiantNexus Team, which seeks to reimagine Sonic 1 by rearranging levels. remixing music, adding features from future games, and readding scrapped ideas in new and interesting ways. Major features: 3 acts of reimagined level design, including one act that has yet to be fully reimagined in any other hack. A miniboss. Massive art overhaul all over the place. Music made by ProjectFM and MechaKnuckles. Menus! A custom splash screen. There's been massive engine overhauls as well, including the Sonic 3 level layout format for massive levels, and the Sonic 3 object manager to go alongside this.