Here is the full list of all 20 Steven Universe: Save the Light achievements.
Collect all other achievements
Perform every fusion and team attack
Win the fight and then go out for pizzas!
Defeat any boss while wearing the CBF Badge
Experience an alternate sequence of events...
Receive every fortune from BOLTRON: SON OF ZOLTRON
Complete the game to 100%
Save Light Steven and the Prism
Recover every Lil' Light Steven
Fully upgrade all weapons at The Forge
Travel to every zone
Perform 10 Perfect blocks in a row
Jump through a big donut
Help Vidalia finish her masterpiece
Complete all the Fish Stew Pizza deliveries
Deliver over 100 damage with one ability
Perform 10 Perfect attacks in a row
Defeat any boss without letting any party members be defeated
Defeat 100 Light Constructs
Defeat three enemies with a single attack