- Back to: Sonic the Hedgehog CD (prototype; 1993-07-12).
The menu on the title screen is reversed, though the options are all the same.
The 712 prototype has a different looking "RAM Data" screen. It is not fully functional and has some bugs that would be fixed in the final:
- The player cannot copy their save file to the Mega-CD's internal RAM if a RAM cartridge is not present or there isn't already a Sonic CD save file copy in the internal RAM.
- Erasing the save file doesn't appear to work.
- It doesn't seem to be possible to replace the save file with one saved in storage.
The D.A. Garden is called "Sound Test" on the title screen.
Exiting the D.A. Garden will lock up the game.
The Visual Mode screen does not have background music, and "Opening" is misspelled as "Openning".
The pencil test hasn't been implemented and cannot be viewed yet. Selecting it in the Visual Mode will just play the opening FMV.
The level select is identical to the "510", v0.28A and v0.51 prototypes.
The preview for Special Stage 6 in the Time Attack menu doesn't animate.
Despite the Title Screen having the proper title, the game is still referred as "CD SONIC THE HEDGEHOG" internally.
Save files created by this prototype can be used in the final game, and vice versa.
Debug mode can be used in Time Attack. It was disabled in the final to prevent cheating.
The robot transporter in the Present doesn't appear to have degraded as much as it has in the final.
Invisible objects that catapult Sonic into ball form (usually found in tubes) will become visible with shield, invincibility or time warp graphics if Sonic has any of those items in effect.
The "S" and Clock monitors have been removed aside from a secret room in Palmtree Panic 3, but the Blue Ring monitor can still be found in a few sporadic locations throughout the game. They also have their effects changed somewhat:
- The "S" monitor, when placed with Debug Mode, not only grants Invincibility and Power Sneakers, it also gives you a Shield.
- The Clock monitor, when placed with Debug Mode, causes other monitors to stop blinking.
- The Blue Ring monitor now functions like an invisible shield, allowing you to take a hit without losing your rings. It can also stack with a regular shield.
Getting all the Time Stones doesn't automatically destroy all robot transporters and thus won't change all futures to Good Futures.
The game-ending "I'm outta here!" Easter egg now causes an instant Game Over as intended, but the camera will still follow Sonic as he jumps off the stage, dying from reaching the bottom of the stage.
The player will always get a bad ending even if the the player has destroyed every robot transporter in the game or collected all the Time Stones. The good ending has been implemented though, and can be viewed in Visual Mode.
The ending FMVs have no music or sound effects, and don't display the "TRY AGAIN/YOU'RE TOO COOL!" messages or the "Presented by SEGA" text at the end.
The jump sound doesn't work properly in normal stages. It works in the Special Stage, though.
The Super Peel-Out doesn't play any sound effects, but the Spin Dash does.
Destroying a badnik plays a different sound rather than the traditional badnik explosion sound.
When you gain an extra life, instead of Sonic saying "Yes!", he says "Yeah!".
Destroying the robot transporter in the Past doesn't play a sound after the explosion.
The goal signpost doesn't make a sound when passing it.
Pausing the game does not pause the music; it simply mutes it.
The time warp sound is different from both the 510 prototype and the final, this time playing a CD audio track that would go unused in the final. It is track #33, whereas it would be track #2 in the final.