|Unused Newtron||These unused sprites can only be found in the Master System version of Sonic the Hedgehog's Green Hill Zone. The animations go unused, but an alternative one is used in Jungle Zone instead. It appears to be a version of the Newtron, which appeared in the 16-bit version of the game.|
|Unused Enemy||These unused Bat sprites can only be found in the Game Gear version of Sonic the Hedgehog's Green Hill Zone. It appears to be a version of the Batbrain, which appeared in the 16-bit version of the game.|
One of magazines shots features the screenshot from possible, earlier build of the original Master System game with the hud spelling "RING" instead of "RINGS".
Unused Marble Zone BGM
Ancient Corp. developed the 8-bit releases of Sonic the Hedgehog, and were evidently going to credit themselves on the game's title screen with the text "©SEGA/Ancient 1991". In the end, however, only SEGA received credit.
Unused level artwork
Game Gear only
Note that some of these objects are used in the Master System version of the game.
|Unused totem pole||These totem poles from Green Hill Zone are used in the Master System version but are left unused in the Game Gear version.|
|Unused corner tile||These corner pieces from Green Hill Zone are used in the Master System version but are left unused in the Game Gear version.|
|Unused checkered spike||A checkered spike. Its purpose is unknown.|
|Unused Sky Base slopes||Some unused slope tiles.|
|Unused platform||This platform has the same tiles as Bridge Zone. Its design almost looks like a small hill.|
|Unused spring and pole||The spring seems to have a checkered pattern and the pole in front has some tiles that look similar to the ones from Bridge Zone.|
|Unused spring||An unused sideways spring.|
|Unused object||The tiles look similar to the ones in Labyrinth Zone. Its purpose is unknown.|
|Unused pillars||Pillars that appear to be meant for Labyrinth Zone.|
|Unused slopes and laser turrets||These objects were meant to be implemented in Sky Base Zone.|
|Unused chain and cannon||These objects were meant to be implemented in Sky Base Zone.|
|Unused shield||An unused sprite from an unused animation.|