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