Sonic the Hedgehog 2 (Sega Master System, Game Gear)

Sonic the Hedgehog 2
Developer: Aspect Publishers: Sega (JP/US/EU/AU), Tec Toy (BR), Samsung (KR) Platforms: Sega Master System, Game Gear Released in JP: November 21, 1992 (Game Gear) Released in US: November 17, 1992 (Game Gear) Released in EU: October 16, 1992 (Master System), October 29, 1992 (Game Gear) Released in AU: December 1, 1992 (Master System) Released in KR: 1992 (Master System) Released in BR: December 25, 1992 (Game Gear), June 18, 1993 (Master System) This game has hidden development-related text. This game has unused graphics. This game has unused items. This game has unused music. This game has a hidden level select. This game has a prototype article This game has a prerelease article

Sonic the Hedgehog 2: featuring Tails as Princess Peach!

Unused Graphics

Character Sprites

Artwork	Name	Description
	"Crying Tails" Animation	Tails crying. Probably meant to be used in the ending cutscene when he is rescued.
	"Bored Sonic" Animation	While the majority of the game's Sonic graphics were copied from the Master System version of the first game, the waiting animation was changed, rendering these three frames unused. They were used in the AutoDemo prototype, though.
	Sonic 1 Death Sprite	Sonic's death sprite from the Master System Sonic 1. The final version uses an updated sprite.
	Under Ground Zone Boss body	The entire body of the boss. Normally, only its head is visible.
	Sky High Zone Boss body	The entire body of the boss. Normally, only its head and neck can be seen.

Monitors

Artwork	Name	Description
	Sonic Monitor	While you can find this in a wall in Crystal Egg Zone, the graphics are obscured. When collected, it grants a continue.
	Question Mark Monitor	May have given a random amount of rings or items, like in the 2-player mode of the Genesis version.
	Grey Sneaker Monitor	May have slowed you down, like the Speed-Down sneaker in the 2-player mode of Sonic 3.
	Arrow Monitor	Most likely intended to be a checkpoint marker, like the 8-bit versions of Sonic 1.

Level Art

To do: There are many more. Sky High Zone Act 2, Aqua Lake Zone Act 1 & 3, and Act 2, Green Hills Zone, Gimmick Mountain Zone, Scrambled Egg Zone Acts 1 & 3, and Act 2, and Crystal Egg Zone Acts 1 & 2 all have many unused tiles!

Artwork	Name	Description
	Under Ground Zone Bricks	Several unused bricks. Tiles similar to the gray bricks were used in the AutoDemo prototype, but they were removed by the final version.
	Under Ground Zone Tunnel	Leftovers from the curved tunnels found in the AutoDemo prototype.
	Under Ground Zone rock	A 32x32 rock that was used in the AutoDemo prototype.
	Under Ground Zone Tiles	Miscellaneous unused pieces.
	Under Ground Zone Floating Platform	An unused floating platform.
	Sky High Zone boulder	This boulder was probably supposed to roll down a hill in Act 1.
	Sky High Zone platform	Another unused floating platform.
	Sky High Zone object	Unknown purpose - another platform?
	Sky High Zone water	Water tiles that were supposed to appear in Act 2. They look similar to the tiles found in the AutoDemo prototype.
	Sky High Zone trees	The trees from Act 1 were apparently supposed to appear in Act 2, but they don't.
	Sky High Zone background	An unused 32x32 background tile that was supposed to appear in Act 2.
	Aqua Lake Zone block	A small additional piece of land. If placed in Act 2, these are fully functional and cause Sonic to slide down much like Labyrinth Zone in Sonic the Hedgehog.
	Aqua Lake Zone waterfall	This waterfall tile was probably gonna be used with the block above.
	Aqua Lake Zone spikes	Unused spikes that were supposed to appear in Act 1 and 3. The only spikes found in this zone are underwater.
	Green Hills Zone grass	While the miscolored grass tile on the left is used in game, an unused, properly colored grass tile exists.
	Green Hills Zone tiles	Unused graphics for background scenery that look like a flower stem.
	Green Hills Zone spring	A diagonal spring in front of the scenery that isn't used anywhere.
	Gimmick Mountain Zone breakable block	A breakable 32x32 tile that isn't used anywhere in the level.
	Scrambled Egg Zone breakable block	A breakable 32x32 tile that looks very similar to the Gimmick Mountain one, still unused.
	Crystal Egg Zone background tiles	Mountain background tiles that aren't used anywhere.
	Crystal Egg Zone tiles	Scenery tiles that aren't used anywhere.
	Crystal Egg Zone flower	An unused flower.

(Source: Sonic Retro,The Spriters Resource)

Gimmick Mountain Title Card

Originally, the level card for Gimmick Mountain Zone used its full name. Due to lack of space on the screen, however, "Mountain" was shortened to "Mt."

(Source: Hivebrain)

Unused Text

A build date string can be found in the ROM at 0x000C0.

Master System (REV00)	MS SONIC THE HEDGEHOG.2 Ver1.00 1992/09/05 SEGA /Aspect Co.,Ltd
Game Gear	GG SONIC THE HEDGEHOG.2 Ver1.10 1992/09/12 SEGA /Aspect Co.,Ltd
Master System (REV01)	MS SONIC THE HEDGEHOG.2 Ver2.20 1992/12/09 SEGA /Aspect Co.,Ltd

Unused Music

A peaceful, ethereal-sounding tune. What this song could have been used for is unknown, but it might have been an early theme for either Crystal Egg or Aqua Lake due to the similar style. The song also has some resemblance to the present theme of Tidal Tempest in the Japanese/European soundtrack of Sonic CD. This song was removed from the Game Gear version, and was replaced by the sound effect that plays when Sonic (and Tails) look up at the stars at the end of the credits. Both of them use $92 as the song value.

Level Select

Master System

While powering on the game, hold Left + 1 + 2 on Controller 2. When the intro sequence starts, release the buttons, then start the game as usual.

Game Gear

When the intro starts, hold Down + Left + 1 + 2 + Start. When the title screen appears, wait for a ring sound to play twice (Tails will wink three times). Release all the buttons and press Start.

Version Differences

To do: This section is WIP: add more detail, elaboration, rip the alternate boss/Power Sneakers/good ending themes, document revision 2.2 of the Master System version, etc.

The 8-bit versions of Sonic the Hedgehog 2 are mostly identical, but besides the resolution, there are some differences detailing the transition from Master System to Game Gear:

• The intro originally started with Tails already kidnapped. On handheld, it starts off with Tails running away as Robotnik's claw catches him. The sky in the intro also changed from a bright cyan to a very dark shade.
• The music during the Master System intro is the title screen music of the Game Gear version; the Master System title screen plays no music, and the Game Gear intro plays the Scrambled Egg Zone track.
• The boss music is different between versions, with the Game Gear version noticeably being mixed into the JP Metallic Madness from Sonic the Hedgehog CD. The Master System boss music was removed completely from the Game Gear version, however, the Game Gear boss music does not use the same sound value as the Master System version. The Master System boss music is $89, but the Game Gear boss music is $94. Attempting to play $89 on the Game Gear version crashes the game.
• Several small changes are present to level geometry and ring layouts across the game. A notable example is a set of rings in Green Hills Zone spelling the word "END" (one of the level designers listed in the credits) was added. These changes are minor and don't appear to be done to make the stages easier to navigate with the restricted view as per the stage changes in the Game Gear version of Sonic the Hedgehog.
• The geometry of several boss fight areas were made smaller to accommodate the smaller fixed screen. For example, the Green Hills arena is much narrower, and Crystal Egg's boss makes the horizontal pipe exit on the left invisible.
• Several boss fights are more difficult. Under Ground's boss now has the rocks bounce at unpredictable heights, Aqua Lake's boss continually moves towards Sonic, forcing him to jump and be bounced away before the orange sphere attack, and Green Hills' boss will now sometimes combine a high leap with a low roll attack rather than just doing one or the other. Crystal Egg's boss is not necessarily harder, but it does not follow exactly the same attack pattern as the Master System version, i.e. if one attacks it during the optimal openings on each play, it will result in the battle playing out exactly the same every time, but those openings and thus exactly the same scenario differs for each version.
• In the Master System version of Aqua Lake Zone Act 2, the entire level is a murky green palette, and the waterline is invisible and at a fixed position near the top; on Game Gear, clean blue water visibly rises and floods the entire stage at the start.
• When Sonic drowns in the Master System version, he sinks with his mouth opening and closing, like the Master System version of the previous game; on Game Gear, he sinks with his mouth open, as in the console games.
• Power Sneakers exist as a one-off powerup in the Master System version, only appearing in Aqua Lake Zone Act 2. When this monitor is broken, a unique track is temporarily played, but it otherwise does not provide its usual speed-up effect. Likely because of this odd oversight, it is replaced by a Super Ring monitor in the Game Gear version. The song was also removed completely from the Game Gear version, and crashes if attempted to play.
• The sound effect when Sonic spins on the wheels and orb in Gimmick Mountain and Crystal Egg is different.
• On Game Gear, "HIRO SSS" is credited in place of "SEMIMARU" and "TOSIYAN" is corrected to "TOSHIYAN" for the Program, and there is an extra credit for "RYU" under Thanks.
• The bad ending music is extended on Game Gear, while it cuts short on Master System.
• The good ending has its own, happy-sounding tune on Game Gear. This song does not exist at all on the Master System Version. This song's value on the Game Gear is $95.
• When Sonic (and Tails) look upon the stars at the end of the credits, a sound effect is now played. This sound replaces the unused track ($92) from the Master System version.
• When Sonic enters the tube that leads to Scrambled Egg's boss arena in the Game Gear version, the boss music starts playing immediately, where in the Master System version, it starts just as Sonic exits the tube.
• The end of act tally counts down points slower in the Game Gear version.