You completed the game as Sonic.
You completed the game as Knuckles.
You earned a Continue.
You collected all seven Chaos Emeralds.
You collected a Chaos Emerald.
You finished the Lava Reef Zone.
You finished the Sandopolis Zone.
You finished the Flying Battery Zone.
You finished the Mushroom Hill Zone.
You collected 100 rings.
You started the game once with each character.
You entered a Bonus or Special Stage.