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