Kaizo Sonic The Hedgehog - The RAGE game is another fan-made ROM hack of the original Sonic the Hedgehog for the Sega Genesis. Similar to other "Kaizo" hacks, its defining feature is its extreme difficulty. It modifies level layouts, enemy placements, and adds numerous traps and obstacles to significantly increase the challenge. The original game's gameplay elements are retained, but the experience is entirely re-imagined for experienced players seeking a high degree of difficulty.  Developed and released independently within the ROM hacking community, it has no official affiliation with Sega or Sonic Team.

Kaizo Sonic The Hedgehog - The RAGE game

Ka-Ge-Ki - Fists of Steel (USA)