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