Sonic the Hedgehog (Genesis)
|Sonic the Hedgehog|
Developer: Sonic Team
This game has unused enemies.
|This page sucks. If you can make it suck less, that'd be awesome.|
Specifically: This page (along with several other Sonic pages) basically steals from Sonic Retro. It's so bad, some of it is plagiarism, i.e. the section about the bumper.
Sonic the Hedgehog is more or less the definitive game of the Genesis in the early 1990s and introduced the world to Sega's new mascot.
One of the most well-known codes in gaming history: press Up, Down, Left, Right on the title screen, then hold A and press Start. In the original revision, the level order is different from the order in normal gameplay.
|Green Hill Zone||Green Hill Zone|
|Labyrinth Zone||Marble Zone|
|Marble Zone||Spring Yard Zone|
|Star Light Zone||Labyrinth Zone|
|Spring Yard Zone||Star Light Zone|
|Scrap Brain Zone||Scrap Brain Zone|
|Final Zone||Final Zone|
Another well-known code. While Up, C, Down, C, Left, C, Right, C is the most common version, a shorter version is C, C, Up, Down, Left, Right. The main requirement for the code is pressing C twice before the final input of Right. After entering the code, press Start while holding A and continue holding A until Sonic appears in the level.
To activate Level Select and Debug Mode, simply enter the Level Select code, push any direction on the D-Pad after the ring sound, then enter the Debug Mode code.
From here, you have access to a variety of things:
- Infinite Time
- Debug Coordinates (in place of score)
- Sprite Counter (in place of time)
- Placement Mode: Press B during gameplay. From there...
- Press A to move forward one object.
- Hold A and press C to move backward one object.
- Press C to place the object.
- Pause Options: press A to go back to the title screen, B to enable slow motion, or C to enable frame advance.
Note that all of these can be seen in-game by using Debug Mode to fall outside the playing area of the Special Stage. It is easier to see them when advancing frame-by-frame by pausing and pressing C.
Labeled as Zones 1-6, they act as solid blocks but have no known use. Dean Sitton, a former Sega of America employee, suggested that they marked which Special Stage the player entered.
Extra life icon for the Special Stages, listed in the instruction manual but never actually appearing in any of them. It is, however, fully functional, and can be placed in any Special Stage. The icon disappears like a ring when touched.
A solid block with a W on it. Its use is unknown, and it has no function when placed in-game.
If you fly above the signpost as an object in debug mode, the signpost's graphics will be glitched once it moves into view, and these monitor images will be visible. None of these monitor types actually do anything, though.
An image of Sonic's unused goggles, leading some to believe it was originally a powerup.
A "static" monitor present in various areas of Scrap Brain Zone the player cannot normally access, such as inside walls. It is possible to break one of them, however, by "digging" into the wall in a jump and popping it (the image of the monitor being a portion of the "zappers"). This can be placed in debug mode.
This "S" monitor also appears in Sonic CD Prototype 510, where it grants the player both extra speed and invincibility. That is most likely the intended function of the monitor here, as a Computer & Video Games issue alludes to a powerup which grants extra speed and invincibility. This suggests that the S monitors were functional at that point in development.
Sonic standing while gasping for air. This was presumably used in Labyrinth Zone and Scrap Brain Act 3.
Sonic holding his breath while running. It is speculated that this was used during the countdown to signify no air is left for Sonic.
A sliding sprite similar to one used in Sonic CD's Wacky Workbench.
Seen in a couple of prototype screenshots in magazines, Sonic appears to be striking a victory pose after passing the signpost.
Spin Dash-esque sprites, use unknown. Some theories are that they were used for a move similar to the Spin Dash or that they are animations for some sort of warp movement, perhaps through winding tunnels. It's also possible that a teleporter like the one found in the 8-bit Scrap Brain Zone would have played the animation.
Sonic falling or shrinking. Their intended use is unknown, although it most likely would have been either an early death animation or an extended falling transition from Scrap Brain Zone Act 2 to 3.
Green Hill Zone
The checkered ball that is part of the final Green Hill boss was originally its own independent object. Earlier in development, Sonic did not have the ability to roll through certain walls and instead used the checkered ball to crash through; this explains why this ability is unique to Green Hill. Magazine pictures have also shown Sonic riding down hills on it.
The two faces here are not in their original palette, but these appear to be an earlier version of the faces on the totem poles of Green Hill. Interestingly, they show how the palette must have changed, because even when placed in the level they are grey, blue, and red.
Found in Green Hill's tileset, and appear similar to the areas used in the underground areas of Green Hill in the 8-bit Sonic 1. These may have also been used for a cut underground area.
Horizontal spikes, rather than the vertical ones actually used in Marble Zone. They are also slightly thinner. They fully work upon placement, though.
Spring Yard Zone
Found in the tileset for Spring Yard Zone, and can be seen in several early screenshots.
Labyrinth/Scrap Brain Zone
A horizontal sprite of the Burrobot.
Star Light Zone
These lights are present in Star Light's data, but not used.
Three machines also in Star Light's data. They appear to have been background objects rather than obstacles.
The left image shows the back of Robotnik's legs, which can't be seen normally. The right image is what is normally seen.
A bumper that uses rosebud graphics, albeit with a small background and an incorrect palette. The ending level shares its debug item list with the Special Stage, so the bumper appears and is usable in both.
Press Start Button
Many early previews of Sonic 1 showed "Press Start Button" on the title screen. While the graphics are still in the ROM, it does not appear due to a bug. You can make it appear by either accessing the secret credits screen in the Japanese version via a cheat code, or using Game Genie code AB3A-DADV.
Splats the Bunny
A Badnik that, despite not appearing in-game, appeared in a set of promotional trading cards for the game, was shown on the box of a series of Japanese Sonic figures, and was featured in the UK Sonic the Comic. When the Nemesis compression format was finally cracked in 2002, the sprites were discovered in Sonic 1.
Some controversy has broken out over Splats' true coloring: though the sprites have Sonic's palette applied to them and the trading card scan appears to have a bluish tint, the quality and validity of the card has been called into question. Other theories to his coloring include purple (for Spring Yard's palette) and green (for Star Light's second palette line).
Found in the original ROM, it was thought that they were meant to give Sonic the ability to breathe underwater due to a matching monitor icon. However, Dean Sitton has gone on record to say the goggles were originally a cosmetic change showing that Sonic was underwater (à la Kirby). Each frame of the graphic fits together with one of Sonic's usual poses:
Unused Eggman Graphics
Purpose unknown, but it is speculated that they may be part of an "alternate ending sequence" in which Eggman explodes in the background while Sonic runs across the ending level in victory.
On the Sonic Team Presents screen, text showing the full names of key staff members and their roles in development is placed behind the Sonic Team Presents text. You cannot see this, however, because both the text and the background color are black. With a cheat code, however, the game will hide the Sonic Team Presents text and change the background color to white, showing the hidden credits. In either ROM, with the region set to Japan, press C, C, C, C, C, C, Up, Down, Down, Down, Left, Right; you should hear a sound confirming this. Then, when the demo starts, hold Down + A + B + C and either press Start or wait for the demo to end.
The credits translate to:
|Design|| Naoto Ooshima|
|Sound Produce||Masato Nagamura|
|Sound Program|| Hiroshi Kubota|
In Green Hill Zone Act 2, there is a Crabmeat at coordinates 10D0 0370, under the section with the moving pillars and spikes, just before the checkpoint. It cannot be seen in gameplay because it is below the camera's boundary, and Crabmeats are programmed to attach themselves to the floor beneath them...but there is no floor beneath it.
Should we include the differences in the Mega Collection bonus edit (most notably the so-called "spike-bug") since it's technically a modified Mega Drive ROM, even though no evidence of official cartridge release exists? Should we also mention the Sonic Jam edition on top of that, which implements the unused skidding effect and includes spin dash/"spike bug" toggle?
3D Sega Classics version differences: Spin Dash, International/Japanese version toggling, Level Select available as toggle in Special menu
A revision was silently released which is more common in the Asian market. Most compilations and re-releases include this altered version. Below are the changes:
- The clouds at Green Hill Zone and on the title screen now scroll from right to left. This became common in most depictions of Green Hill in the series.
- The water in the game has been given a ripple effect not unlike that of Sonic CD.
- The level select is now rearranged. In the initial release, the Zones were listed in a pre-release order that doesn't represent the final game.
- The game checks and detects if it is being played on a Japanese console, though it is not regional lockout – it merely affects small things on the title screen like trademark and level select code.
- The points system has been slightly altered: lives are gained every 50,000 points, and the final boss now awards 1,000 points in defeat.
- Minor programming changes of certain properties such as Caterkiller's nuances, lamppost / game over and drowning music exist.
- Generally, the game code is tighter, more efficient, and removed unnecessary remnants like certain unused sprites.
Labyrinth Zone's Extra Ring
There is one extra ring in Labyrinth Zone Act 1 of Revision 01. After the player presses a button near the two rising platforms, a platform spawns above, something few people know about. It's possible to reach this platform with a well-timed jump, and if the player rides on it, it'll take them to an alternate path which may have an extra ring.