A "greatest hits" compilation of levels inspired by Sonic 2
, Sonic 3
, and Sonic & Knuckles
. The player first selects one of the three games, each spanning multiple bosses and five levels based on one zone from the original games (Emerald Hill for Sonic 2
, Angel Island for Sonic 3
, and Mushroom Hill for Sonic and Knuckles
). The player can then select from Sonic, Tails, or Knuckles, each of which has their unique abilities, except for Knuckles, who can neither glide nor climb. Sonic 3
's bonus stage is also included.