The collection includes:
- Sonic the Hedgehog 3
- Sonic & Knuckles
- Sonic 3 & Knuckles
- Blue Sphere (in options dialog as "Special Stage Mode")
The European and North American versions of the collection also include Sonic the Hedgehog The Screen Saver which the player can customize Windows with Sonic themes, wallpapers, icons, and music from Sonic 1, 2, 3 & Knuckles, and the Japanese soundtrack of Sonic CD in 11 kHz WAVV format. However, in Japan, Sonic & Knuckles Collection and Sonic the Screensaver were released separately on the same day.
The gameplay is identical to their Mega Drive / Genesis counterparts, but all of the music is emulated in MIDI format. Some tracks (Carnival Night Zone, IceCap Zone, Launch Base Zone, the Sonic the Hedgehog 3 Credits theme, Knuckles' theme in Sonic the Hedgehog 3, the sub-boss music from Sonic the Hedgehog 3, and the Competition main menu) were replaced with music taken from an early prototype of the game. One possible explanation for this is that the final pieces of music from the Genesis version used sound effects not contained within the general MIDI standard, and many sound cards at the time of release did not have the capability to play additional samples along with the MIDI. Another explanation for the replacement is that the songs were replaced due to legal reasons, because connections could be made between similar songs by Michael Jackson.
This game is virtually impossible to play in windowed mode on any system with a CPU faster than 350 MHz, because the game does not have proper speed-limiting routines in this mode. However, the timings used by the game are based on the monitor's refresh rate. Switching the game to fullscreen mode lets the game play properly, no matter what your system speed is. In windowed mode, the game can be played at the correct speed whenever the screen refresh rate is at 60 Hz. Sega has also provided a patch to fix this problem without reducing the refresh rate.
- The original music tracks used for Carnival Night Zone, IceCap Zone and Launch Base Zone originate from the 3 November 1993 prototype of Sonic the Hedgehog 3.
- The sound test was featured in the options mini toolbar for the game, because a glitch would occur and the game would reset if the player tried to listen to a song.
- Mushroom Hill's Act 1 music has a straight rhythm instead of shuffle, and the beginning sound is removed for this compilation.
- A song was included in this compilation that was originally unused in the 3 November 1993 Sonic the Hedgehog 3 prototype. The song also bears some resemblance to the theme of "Green Hills Zone" and its vocal counterpart, "Sonic - You Can Do Anything" from the Japanese/Euro Sonic the Hedgehog CD soundtrack.
- This game, along with Sonic the Hedgehog CD and Sonic's Schoolhouse, was one of the demos included in the Hershey's sampler.
- Search | Pegi Public Site. pegi.info. Retrieved on 3 May 2021.
- Lynch, Joe (26 January 2016). Michael Jackson Wrote 'Sonic the Hedgehog 3' Music: Crazy Theory Confirmed? (English). Billboard. Retrieved on 18 April, 2018.
- Sonic the Hedgehog 3 (Nov 3, 1993 prototype). HiddenPalace.org. Retrieved on 10 May 2021.