This article pertains to the beta elements from Sonic the Hedgehog CD.
Prototype 510
Discovered by a group of fans in the summer 2000, this prototype dates itself to 10 May 1993, making this the earliest known beta of the game, and thus features many differences from the final release of Sonic the Hedgehog CD.
List of changes
Bosses
In Palmtree Panic, the EGG-HVC-001 was meant to have claws instead of Bumpers.
In Quartz Quadrant, the conveyor belt boss had a dull-blue palette, and the spike wall was much more simplistic in its design.
The Stardust Speedway boss has not been implemented yet.
Music
The title screen music and the Japanese/European Power Sneaker music was changed dramatically during development. The beta Power Sneakers music is a high energy remix of "Sonic - You Can Do Anything".
| Music | Description |
|---|---|
 | Beta Title Theme |
| Beta Speed Shoes Theme |
Stages
Zone 3 of Palmtree Panic uses placeholder graphics for the scenery that more resemble simple recolors of the Present time period in both Futures. Not that this is not the case with Zones 1 and 2, which both use their proper graphics that would go on to be used in the final game.
Tidal Tempest uses different palettes for when underwater, though these are likely placeholder graphics since the actual palettes are used for the Time Attack menu.
The conveyor belts in Quartz Quadrant were meant to be activated by pressing down on buttons rather than running past switches like in the final game. Additionally, there is a monitor displaying Sonicās face that can be found in the Good Future of Zone 1 that goes unused in the final game. Of note is that this sprite was eventually restored and used in the Good Future of Zone 3 in the 2011 remake of the game.
Many of the colors in Wacky Workbench are different from the final release, including a slightly greener background in the present, and a blue foreground palette for the past rather than a green one. The electrical conduits also feature pointed nubs intead of round ones like in the final.
Likewise, many sprites in the Past time period of Stardust Speedway are blue instead of yellow. The Good Future is also completely blue instead of purple like in the final release.
Metallic Madness features many changes that go completely unused in the final game, including but not limited to trapdoors similar to the ones in Scrap Brain Zone, a set of scales that shift according to Sonicās weight, and bottomless pits in Zones 1 and 2 (Which only appear in Zone 3 in the final game).
Unused Sonic sprites
| Image | Description |
|---|---|
| This sprite shows Sonic being electrocuted, revealing his skeleton. Would be reused in the 2011 remake when being damaged by electricity in Wacky Workbench. |
| Sonic with his eyes closed. |
| A topdown sprite of Sonic falling. |
| Sonic running while swinging his arms, possibly for while underwater. |
| Sonic looking up behind him. |
| Sonic sneezing. |
| The regular Death/Drowning sprites, only upside down. Interestingly, Tails got his own version of these in the 2011 remake, also unused. |
| Sonic appearing to grab onto something. |
| An alternate version of Sonicās shimmy animation. |
| Sonic appearing to be dangling from something. |
| Sonic pushing his chest out in front of him. |
| An unused frame of Sonicās turning animation. |
Beta Bonus Stage
In an early prototype version of Sonic CD, there was a bonus stage similar to the Special Stages in Sonic the Hedgehog (1991).
R2
A mysterious scrapped stage known as R2 can be found in the game's files. It is unknown what was supposed to be of the stage though it was to be placed between Palmtree Panic and Collision Chaos.
