Endings (SCD)

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There are 2 endings in Sonic CD, determined by whether you finish the game with all the Time Stones or not.

After finishing Metallic Madness and defeating Dr Robotnik you are treated to a short animation of Sonic, with Amy, escaping the destruction of Robotnik's influence on the Little Planet. Sonic leaves Amy and runs off, watching the Little Planet break away from the chain that ties it to the ground, the planet begins to glow in the image of either Sonic (if you finished the game with all the Time Stones) or Dr. Robotnik (if you missed any Time Stones). Then the planet pulls into the air and explodes, scattering sparkles if you finish the game with the Time Stones.

Then the credits roll, along with more animation on Sonic travelling through the zones. Once the credits have finished there is one of two small endings. If you finished with all the Time Zones, the sparkles that fall from the Little Planet fall to the ground and flowers grow. But if you missed any Time Stones, the Little Planet reappears, chained to the ground.