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