Here is the full list of all 19 Juju achievements.
Defeat Frobos and collect his key part.
Defeat Robos and collect his key part.
Defeat Octobos and collect his key part.
Defeat Cobos and collect his key part.
Defeat Calypso.
Complete a level in co-op.
Gather all Coins on one level.
Gather every Coin in the game.
Complete one unlockable level.
Complete all unlockable levels.
Unlock a new skill.
Unlock all skills.
Find a secret teleport.
Find all secret teleports.
Collect more than 100% of ambers in any level.
Complete any level without losing a heart.
Complete any level without collecting an amber.
Hit 3 enemies with one dash.
Make 4 enemies dance at once.