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