Here is the full list of all 32 The Metronomicon: Slay The Dance Floor achievements.
Survive a story song without healing any party member.
Survive a story song without killing an enemy.
Apply six buffs to one hero at the same time.
Defeat every arena challenge.
Defeat every arena challenge on hard.
Purchase every ultimate weapon.
Succeed in every single sidequest.
Survive every song in Story Mode.
Survive every song in Story Mode on Hard.
Beat the final challenge's omega boss.
Deal at least 5000 hp damage in one strike as Gwen.
Kill five enemies in a row with a single attack.
Make five arena challenges your chump
Unlock Sara's laboratory.
Save the world of Koras from Dancemageddon.
Conquer one challenge in the school arena.
Decompile a fearsome Dance-o-bot.
End the dancing of a great Candy Dragon.
Dethrone the Wraith King in the Haunted Kingdom.
Succeed in beating five sidequests.
Survive your first 10 songs in Story Mode.
Destroy the Speyeder of the Wild Forest.
Attain a 300 note streak.
Perform a perfect meteor attack counter.
Succeed in your first story sidequest.
Attain a 100 note streak.
Unlock your first bonus song.
Perform a perfect Solo-Lane Team Attack.
Perform your first upgrade to the school.
Beat a fifty song playlist without ever pausing.