Sonic the Hedgehog (Sega Master System, Game Gear)

The 8-bit ports of Sonic the Hedgehog scaled down the 16-bit game and included the all-new Bridge, Jungle, and Sky Base (not to be confused with Sky Chase) Zones. Given the limitations, it isn't too bad.

Although they're mostly the same content-wise, the Game Gear version has some unused sprites the Master System version doesn't, and vice-versa. The Game Gear's smaller screen also meant that things had to be scaled down, resulting in the Green Hill boss being laughably easy.

The Master System version also holds the distinction of being the last game released for the console in North America.

Sub-Pages#

Development Info Prototype Info Prerelease Info Bugs Version DifferencesLots of things sure can change when porting to another console, then emulating it.

Unused Graphics#

Level Art#

Artwork	Name	Description
	Green Hill Totem Pole	Used in the Master System version, but not the Game Gear one.
	Green Hill Corner Tile	An unused corner piece.
	Bridge Zone Tiles	A spring in front of checkerboard, and a pole in front of some sky tiles. The bridges in this Zone are never high enough to hit sky level.
	Jungle Zone Spring	A spring not set on grass. Probably intended for Act 2.
	Labyrinth Pillars	Some unused big and small pillar tiles! These were created specifically for the 8-bit versions, and have no equivalent in the Genesis version.
	Sky Base Tiles	A chain facing southeast and an unused cannon facing northeast.
	Sky Base 3 Tiles	Some unused slopes, and what appear to be laser turrets. The latter tiles are not in the Game Gear version.

Objects#

Artwork	Name	Description
	Ground Segment	Appears amongst the object tiles for Bridge Zone. It almost looks like the top is melted.
	Door?	Appears amongst the object tiles for Labyrinth Zone. Perhaps it was intended to be a switch-operated door, like the ones in the Genesis version?
	Unused Newtron	An equivalent of the red-eyed Newtron's flying animation from the Genesis version, found in Green Hill's tileset in the VRAM. Despite always having red eyes in the 8-bit versions, they only ever act like the yellow-eyed ones from the Genesis version, and are only found in Jungle Zone at that. Master System version only.
	Shield	May be an early shield animation. Game Gear version only.
	Unused Enemy	Graphics for the enemy Batbrain appear among the Green Hill objects, and were probably meant to be used in the caves of Act 2. The Genesis version uses them in Marble Zone, not present in either 8-bit port. Game Gear version only.

Title Screen#

Artwork	Name	Description
	"PRESS BUTTON" A	This goes unused in the Master System version, as it simply reads "PRESS BUTTON". Perhaps the prompt was meant to read "PRESS A BUTTON"? This is used in the Game Gear version though, as that reads "PRESS START BUTTON".
	Ancient	Ancient handled the 8-bit ports of Sonic 1 and were evidently going to credit themselves on the title screen with the text "©SEGA/Ancient 1991". In the end, though, only Sega received credit. Notably, this graphic appears in a prerelease screenshot of the title screen.
	1992	A 1992 copyright date, Game Gear version only. Most likely present just in case the game was delayed, since the Game Gear version came out in December 1991. Appears in place of the 1991 copyright in the American and European manuals.

Early Credits Screen#

An early version of the credits screen can be found in the Master System version at ROM offset 16AEE. The triangles in the background were replaced with yellow and blue stars in the final version.

Unused Audio#

A rendition of Marble Zone's theme, present in the Master System version's ROM at offset CD0A. This and the unused Batbrain graphics (present only in the Game Gear version) suggest that Marble was intended to be included in the 8-bit ports but was cut due to time or space issues.

This sound echoes twice. Might have been used for an early death sound effect. This would later be used in the Game Gear and Master System versions of Sonic Spinball when grabbing a Chaos Emerald.

A heavy bubbling sound. May have had a use in Marble Zone before it was scrapped?

A sound similar to the bumper sound, but at a higher pitch. Probably based off the Genesis version, as it is the same pitch.

Sounds like an alarm. May have had a use in Scrap Brain and/or Sky Base?

Unused Text#

Developer Text#

A copyright string starts at 0x3B:

Developed by (C) 1991 Ancient - S Hayashi.

Filler Text#

A text string (with minor variations) used as filler in the ROM banks.

'1991 (C)Ancient. (BANK0-4)
SONIC THE HEDGEHOG
 Master System & Game Gear Version.  

'1991 (C)Ancient. (BANK8-11)
SONIC THE HEDGEHOG
 Master System & Game Gear Version.

'1991 (C)Ancient. (BANK12-15)
SONIC THE HEDGEHOG
 Master System & Game Gear Version.

Unused Palettes#

In the Sega Master System version, a few palettes contain different colors before they are overwritten by palette cycles.

Bridge Zone#

The mountains use gray instead of purple, and the rocks use purple instead of green. Interestingly, the rocks use purple in the Game Gear version.

Jungle Zone#

The background uses purple instead of pink.

Special Stage#

The dark purple is a different shade.

Regional Differences#

Like the Genesis game, the Japanese version removes the trademark logo.

Japanese Game Gear	International Game Gear

Shinobu Hayashi has different nicknames depending on the region. It was likely changed due to "Pinbot" also being the name of a well-known pinball game. The international versions also fix a typo in "Game Programmer".

References#