These are cheat codes for Sonic & Knuckles Collection which can be accessed by inputting button sequences or by various other methods.
- Zone Select/Sound Test: While in Angel Island Zone in either Sonic 3 or Sonic 3 & Knuckles, jump on to one of the swinging vines, then press then hold ALT + R to soft-reset the game and return to the title screen. After being taken back to the title screen press twice and select the Sound Test option. You can select any zone you want to, unless playing Sonic 3 in which case Sonic & Knuckles zones can't be selected. Unlike the Genesis/Mega Drive Version, there is no way to access this screen in Sonic & Knuckles alone since there isn't both an & button for the player to use, unless Debug Mode is enabled in the S3K.ini file (details below).
- Play in any level as any character: In Sonic 3 & Knuckles, start the game with the any character. Enter the Zone select code and then soft-reset the game. At the title screen press arrow key and you will be taken to the Zone Select menu. Normally, specific levels can't be chosen with specific characters (I.E. Knuckles in The Doomsday Zone). Go to Mushroom Hill Zone. Grab onto a pully and re-enter the Zone Select code. Now go back to the Zone Select menu. Now, any zone will be playable using the character that was chosen.
- Take a screen capture: To take a picture of the gamescreen press "F9" at any time. Then go into the Sega folder in the C Drive. From there locate the S3k folder and the image will be labeled Cap with numbers following it. This only works while debug is enabled.
Secret INI file settings
By creating a file in the folder C:\Windows (where C is the main partition for Windows) named S3K.ini, additional cheats can be enabled by adding options to the file, similar to the special debugger option in the Sonic CD INI file. Type the following into the file:
Nine options can be configured here:
- MukaiFrameDrop: This option is enabled by default, and allows for a higher framerate on slower machines (by 1997 standards); however, on modern systems, it makes the game run too fast. Set to 0 to disable it and restore a proper framerate in windowed mode on modern systems.
- DebugMode: Enables debug mode. When enabled, numeric keypad keys 1, 2, and 3 act like Mega Drive buttons , , and , respectively. (The other keys maintain their configuration as set in the Options menu.)
- EnableFrameDrop: Enables frame dropping. Useful for slower machines.
- ShowFrameCount: Show an FPS counter onscreen.
- EnableFrameCapture: If set to 1, maps F9 to a screenshot function. Press F9 while playing to take a screenshot in Windows BMP format.
- UseModeX: Use VGA Mode X for 320x240 in fullscreen. Probably not useful on systems running Windows NT-based operating systems (e.g. Windows XP and later).
- NoSoundEffect: If set to 1, disables sound effects.
- CDCheckEnable: If set to 1, requires the Sonic & Knuckles Collection CD to be present. Set to 0 to disable the CD check.
- SonicGameMode: Default game mode to use when starting the executable directly. Set to 0 for Sonic 3 & Knuckles (default), 1 for Sonic & Knuckles, or 2 for Sonic 3.
This makes some codes or functions that were originally impossible, such as zone select in Sonic & Knuckles alone, switching characters in the zone select menu, and Night Mode (Sonic 3 only) possible. It also allows use of the Sound Test option during the actual game.
With the help of a save file editor such as this one, one can edit values for save files in the game. (It is also possible to use other methods of editing by modifying the Sonic3K.bin file, but these are generally more user-friendly.) Because Knuckles and the Flying Battery Zone were planned for and still have existing data in Sonic 3, they are selectable values as well. Unlike the original game, however, the gameplay engine used for Sonic 3 in this specific compilation is actually based upon the Sonic & Knuckles engine, therefore Knuckles and Flying Battery can be used/accessed in Sonic 3 without error. However, because only Sonic's/Tails's boss triggers are in place, Angel Island Zone Act 2 and Launch Base Zone Act 1 are impossible to complete as Knuckles. For some reason, Knuckles's boss for Angel Island Zone Act 1 is still present. Launch Base Zone Act 2 can't be completed without gliding over to Sonic's boss area from his boss area and clearing the game with Knuckles will cause it to crash since he never had an ending programmed for Sonic 3 alone.
Flying Battery is sort of an odd stage. Clearing it and resetting the game will advance the player to the IceCap Zone. Continuing to play it after clearing it will allow the player to play through all of the Sonic & Knuckles zones starting with Sandopolis Zone. Clearing the Sonic 3 & Knuckles game will give the player the normal credits and ending based on how many Chaos Emeralds you collected, but when s/he gets back to the data select screen, the file that the player was using is redirected to Marble Garden Zone for some reason. Once the player clears Flying Battery, it can't be accessed again unless another file is created that can access it.
Another oddity with the S&K zones in Sonic 3 is that Special Stage Rings are only usable if you have less than 7 Chaos Emeralds, a behavior also exhibited by the Sonic 3C prototypes. If you have all 7, you simply get 50 rings.
- Play as Knuckles in Sonic 3
- First, enter the Zone Select code for Sonic 3 and soft-reset the game.
- Then, go to the Zone Select and select Special Stage 1. This will take you to the "Blue Sphere" minigame. Press Enter/Return when the CODE option is highlighted to change the star on the sphere icon from blue (Sonic) to red (Knuckles). If you're using a gamepad, press (or whatever is mapped to "Button 1") when the CODE option is highlighted.
- Finally, soft-reset to return to the Sonic 3 title screen. Go to the Zone Select menu and select any level, bar any S&K exclusives to play as Knuckles in that level. Don't go to the Data Select menu, though, or else you'll have to do this over again. Do note that some levels can't be completed as Knuckles and the game will crash when Knuckles attempts to do his ending pose after defeating the final boss.
- Character Swap
- Enable the Zone Select code in either Sonic 3 or Sonic 3 & Knuckles and soft-reset the game.
- Now enter it, and pick Special Stage 1. Press Enter/Return when the CODE Option is highlighted to swap between Sonic and Knuckles (or vice versa), and soft-reset and return to the Zone Select screen with your desired character. You can come back to this screen at any time to swap between the two without losing Emerald data or having to enter the Data Select menu.
- Easy Game Clear
- In either Sonic 3 or Sonic 3 & Knuckles, enable the Sound Test option on a saved game file and soft-reset the game.
- Then, head to the Sound Test menu and select the final zone based on your character and the game being played (i.e. in Sonic 3 alone this would be Launch Base Zone). When you clear the zone, after viewing the credits, go back to the data select screen. You'll see that the game file you were using is cleared.
- Easy Chaos Emeralds: Sonic 3 alone
- First, enable the Sound Test menu cheat code, and soft-reset the game.
- Now, select Special Stage 2. This warps you to the special stage.
- Successfully get the Chaos Emerald. After the results show up, soft reset the game and repeat these steps until all 7 Emeralds are collected. This data is transferred to your Game Save window.
- Easy Super Emeralds: Sonic 3 & Knuckles
- First, enable the Sound Test cheat code, and soft-reset the game.
- Now, (at least) play through the Sonic 3 levels of the game, and sometime during that be sure to collect 7 Chaos Emeralds. Once you get to Mushroom Hill, go to the first Giant Ring and jump on any gray emerald so the Sonic & Knuckles special stages are set to play. Soft-reset again.
- Go back to the Sound Test menu and select Special Stage 2. Upon getting the Super Emerald, reset, return to this menu, and do the same thing again. Like Sonic 3, in Sonic 3 & Knuckles, this data is also transferred to your Game Save window.