Sonic introduced the eponymous character and Eggman, Sonic 2 added Tails and Knuckles ... theory hints that Sonic 4 could adapt Sonic CD, the 1993 game that features time traveling and the ...

It is then finally confirmed that Sonic CD indeed takes place before Sonic the Hedgehog 2 and the rest of the old 2D games, with the 2017 throwback Sonic Maina and 2023’s Sonic Superstars being ...