Time Stones
From Sonic Retro
File:Timestones.gif
Complete set of Time Stones.
Time Stones are the equivalent to Chaos Emeralds in Sonic CD. The Time Stones are found on Little Planet and allow anyone who can collect them all to gain control of time itself. Dr. Eggman tries to collect them in order to take over Little Planet, and Sonic tries to collect them to save the Little Planet. If you are able to collect all of the stones early in the game, there will be no need to travel to the past, because the future automatically becomes good. If you don't have all the Time Stones, you must travel to the past to undo the damage Eggman has done. Should the player opt for doing the latter, it is possible to obtain the good ending without collecting a single Time Stone.