Here is the full list of all 21 Before the Echo achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
See the hidden ending.
Synthesize Iridium.
Synthesize every recipe in the game.
Learn all spells.
Beat the game on any difficulty.
Defeat an enemy with less than one second remaining on the clock.
Defeat an enemy using only poison spells.
Defeat an enemy within eleven seconds.
Defeat an enemy on the seventh floor using only Arclight.
Obtain every droppable item in the game at least once.
Discover the name of she who controls fate.
While learning a spell, achieve 100% accuracy for the entire song.
Get her back.
Successfully complete a synthesis at 25% odds of success or lower.
Trigger Boost a Trigger Boost.
Queue up five spells in a row.
Recover over 150 mana in a single battle, and win.
Obtain all three droppable items from any single enemy.
Defeat the Holiday Whompa.
Successfully defeat your first enemy.
Complete a battle without failing a spell.