A Game Boy game was developed by Beam Software but never released. An altered version of their game Baby T-Rex, the game was pulled from distribution just before release when the BBC revoked the license but not before it received a negative review in Game Zone magazine.
BrazSonic 20XX is a reboot of the BrazSonic series set in 20XX's Brazil, where the congressman Dr. Corruptnik, who dreams of being President of the country, seeks the Corruption Emeralds to make it true. However, his ambition implies chaos and destruction to the lands and citizens. Then the hero BrazSonic will come into the scene to stop him!
Sonic and his friends found out about the Cyberspace and its inhabitants, and Robotnik is using this world to create his empire, now everyone has to try to save the Cyberspace with the power of the Cyber Emeralds.
Project 32X is a fan game that attempts to revive the original Sonic Mars/Sonic 32X project.
Sonic the Hedgehog 2: Crash! is a J2ME port of Sonic the Hedgehog 2 released in 2008. The game is a continuation of Sonic the Hedgehog 2: Dash! and features the last few zones of the game.
Knuckles the Echidna in Sonic the Hedgehog was a planned add-on for Sonic the Hedgehog which allowed you to play as Knuckles by attaching the cartridge to Sonic & Knuckles. The game was only previewed once in volume 44 of SEGA Megazone.
The game was later replaced by Blue Sphere in the final release of Sonic & Knuckles.
Nandemo!? Taihoman is a cancelled action platformer that was in development by Namco around 1995, planned to be released on the Super Famicom / SNES. A short preview of the game was also published in EGM (April 1995 issue), but in the end the game was never released in any region.