Japanese Revision 1, Difference 1:
Ripple effect in the Labyrinth Zone water (pictured right) compared with still water in the original version (pictured left).

Japanese Revision 1, Difference 2:
More sophisticated parallactic scrolling effect for backgrounds of Green Hill, Marble and Spring Yard Zones.

Japanese Revision 1, Difference 3:
The level select screen has been changed to reflect the actual order of the zones (pictured right), instead of the internal ROM level order (pictured left).

Japanese Revision 1, Difference 4:
Unnecessary data (mostly unused graphics) has been removed to make room for additional code.

Japanese Revision 2, Difference 1:
Originally, there was a bug where if Sonic was hurt by spikes, he would be killed by the same spikes if he landed on them a second time. This bug has been fixed.