Sonic CD Plus Plus (also known as Sonic CD ++) is a hack of the 1993 Sega/Mega CD game Sonic The Hedgehog CD. it incorporates new gameplay aspects to the original game.
The hack plays much like Sonic CD: you can move with the D-Pad and jump with the A/B/C buttons. Ducking is done by holding down on the D-Pad, and looking up is done by holding up.
Ducking and pressing a jump button will make the player enter a spindash, which uses the version from Sonic The Hedgehog 2 (where the power of the spindash is increased when repeatedly tapping a jump button). Releasing the D-Pad will cause the player to dash off rolling at the built-up speed. Similarly, holding up and pressing a jump button will result in a 'Super Peel-Out'. Letting the player's character (in this case, Sonic) built-up speed reach maximum, will cause the player to dash off.
if in a rolling state and not on the ground, pressing A/B/C will make the player dash in the air. Sometimes, the player will home-in on enemies if in a close range. This feature is based off it's appearance in Sonic Megamix. If not in a rolling state, pressing A/B/C will put them in said state.
- By default, the music is absent, excluding the past themes of each level and the logo jingle. They can be re-added when burning the hack onto a disc.
- The ability to enter a roll in the air and do air dashes/homing attacks, including the Sonic The Hedgehog 2 spindash and Sonic The Hedgehog CD Super Peel-Out would be made available with the Sonic Max Engine for Game Maker Studio 1.4.
- The hack started out as a challenge. Mad Echidna has set out a 100 dollar bounty to who ever could get the Sonic 2 spindash into the game.