Sonic 1 - Back to South Island is a Sonic 1 hack made by HyperSonic16.This hack includes new audio, new stage/special stage layouts, new sprites, SPINDASH!!!!!(of course a spindash XD), New level art, and a bunch of badniks(Thanks Robuttnik!) You all are probably expecting a story, so here it is, nice and sweet:Story:Its the Christmas season, and everyone is doing their thing. Tails and knuckles go off to celebrate Christmas on Angel Island. While this happens, Sonic decides to go back to South Island (hence the name of the hack), to celebrate and check up on the flickys. Eggman, strangely had a similar idea, but he plans to robotize the flickys, and rebuild his base. When Sonic arrives, he finds a bunch of badniks, and he immediately knows that Eggman is there. So sonic, being the hero he is, he travels out to stop eggmans plans.

Sonic 1 The Blue Blur is a hack of Sonic the Hedgehog for the Sega Mega Drive/Genesis, created by Scwha. It gives each Zone totally new palettes and layouts, with the latter designed to be more difficult than those of the original game.

A great hack for Sonic the Hedgehog hack made by MarkeyJester features new enemies, layout, music,etc..Credits:3rd Act Layout - Gallium Grant.Gameplay Testers - iojnekns, snkenjoi, EditChrisBug finders - DAGarden, qiuu, Selbi, SonicVaan

A work in progress hack based on sonic the hedgehog made by Animemaster.This was meant to be a little side project to Sonic 1: Sonic CD Edition I was having problems so I starting something really small. I liked the idea, and ran with it.Robotnik has got a plan to go back in time, but not like in Sonic CD, further back. I feel like he's done this before though. It's a beta, so there are unfinished art and stuff.

Sonic 1: The Special Stages is a hack of Sonic 1 by SonicVaan. This hack removes standard Sonic gameplay and replaces it with the Special Stages which normally were only accessible by the Giant Rings at the end of each stage.The actual special stage layouts have been touched for every stage.This hack is actually on hold. Future releases are not to be expected.

Sonic 3 & Knuckles: The Challenges is an award-winning hack of Sonic 3 & Knuckles by ColinC10. In this hack the player must complete various levels from S3&K, which newly feature specific challenges to complete, e.g. collecting a certain number of rings or protecting Tails from danger. Completing challenges unlocks more challenges, and players' progress is automatically saved to SRAM.

Sonic And The Mystic Gems (previously known as Sonic 1 Harder Levels) is a hack made by Eduardo Knuckles and his team Harder Project of Sonic the Hedgehog on the Sega Mega Drive. It began in 2005 with the simple purpose of being a generic Sonic 1 for Sega Genesis with increase difficulty and revamped versions of the original levels. But now, it's going to present a completely new gaming experience with a new style of level layouts full of paths everywhere among new enemies, new objects, new character abilities, new menus, completely different styles of the Sonic 1 special stages and much more!Credits and Special ThanksMistergambit for his Spring Yard Zone and Labyrinth Zone level art used in the game.Tweaker for his information regarding music importing, bug fixes and the speedcap removal.HPZMan for the new sound driver instruments and the dynamic tile-set system.Selbi for some new exclusive ASM things and improvements.Master3k for sending and fixing some music.nineko for creating the xm3smps tool which was essential for the creation of some songs. Special credits to him for the different songs per act system used.SCAA for their art.Puto for his tutorial to add Spin Dash.FraGag for his tutorial to fix the spike bug.SonicVaan for beta testing.HCKTROX for the lead programming and bug fixing.GenesisFan64 for the save screen menu, for some fixes related to the fade-out and others.MarkeyJester for lots of important code and a whole load of others.Irixion for beta testing.PsychoSk8r for his the dynamic palettes tutorial.Esrael for fixing essential things in the new sound driver.Prilix Bõkun for bug searching and beta-testingEstlib for various art stuff related to levels and for additional help with creation of gimmicks and objectsDJ. Joker27 for his very big importance in specific level and misc musicMighty Arnold for additional support with beta-testing and level layout designKenny0989 for additional support in the music department Special credits to Harder Project's Team by all the useful exclusively things used in the project.