Here is the full list of all 38 Sonic Superstars achievements.
Used Sonic's Drop Dash to defeat 100 enemies.
Cleared Zap Scrap in Frozen Base without taking damage.
Defeated the true boss.
Cleared Trip's story.
Collected 10,000 Rings.
Turned super using the 7 Chaos Emeralds.
Used the White Emerald power "Extra".
Used the Yellow Emerald power "Slow".
Turned Lagoon City's Goal Plate into a pile of fruit.
Used the Green Emerald power "Ivy".
Collected 200 or more Rings when clearing a Stage.
Used the Light Blue Emerald power "Water".
Cleared all of EGG FORTRESS.
Cleared all of FROZEN BASE.
Cleared all of CYBER STATION.
Cleared all of GOLDEN CAPITAL.
Used the Purple Emerald power "Vision".
Cleared an ACT "Fruit".
Cleared all of PRESS FACTORY.
Used the Goal Plate to reveal the hidden Item Box.
Cleared all of SAND SANCTUARY.
Cleared all of LAGOON CITY.
Cleared all of PINBALL CARNIVAL.
Cleared all of SKY TEMPLE.
Used the Red Emerald power "Bullet".
Cleared all of SPEED JUNGLE.
Cleared all of BRIDGE ISLAND.
Cleared 1 Bonus Stage.
Used the Blue Emerald power "Avatar".
Cleared a Stage with a friend.
Used Tails' aerial attack to defeat 100 enemies.
Used Knuckles' glide to defeat 100 enemies.
Used Amy's Hammer to defeat 100 enemies.
Used Trip's double jump to defeat 100 enemies.
Collected 100 Medals from Bonus Stages.
Collected 600 or more Rings from ACT "Fruit".
Defeated 1,000 enemies.
Defeated the gold enemies in all Stages.