Winter Hill Zone: The graphics that are used are unlike any descriptions ever given of the winter level, other than the winter setting.Emerald Hill Zone: Contains prototype layout elements, and the Coconuts Badniks are replaced with the scrapped Snail badniks.Final Zone: The only alteration is the addition of 3 rings at the start of the zone.Green Hill Zone: This, like the rest of the Sonic 1 zones, is entirely unchanged from its original appearance.The order of levels is directly as shown in the newly implemented Data Select menu: More information on the various lineages and their history is detailed in the section “Other versions” below.Ī hack similar in concept, called Sonic 2 Long Version, has been released by another hacker, Sonic Hachelle-Bee. The main version of this hack is entitled Sonic Delta 40 Mb and was based upon the Simon Wai prototype, before version 0.24 transferred the codebase to ‘revision 2’ of Sonic 2 from Sonic Compilation and before version 0.29 transferred to the Sonic the Hedgehog 3 & Knuckles codebase. Several original boss fights have also been created for the hack. Various features of Sonic Delta 40 Mb, common across the series despite the existence of several versions/branches of the hack, include the use of art and music from the betas and Sonic the Hedgehog and re-implementation of badniks that had been removed from the final game. Sonic Delta 40 Mb (formerly Sonic 2 Delta) is a groundbreaking series of ROM hacks by famed Sonic scene member Esrael Neto, which restores several deleted levels and prototype elements to Sonic the Hedgehog 2 for the Sega Mega Drive.

Source code for delta emulator