Here is the full list of all 19 BIT.TRIP FLUX achievements.
Get a PERFECT score in Catharsis
Get a PERFECT score in Perception
Get a PERFECT score in Epiphany
Chained 500 Beats
Beat the game, from start to finish, in one sitting
Enter Meta Mode in each level
Block 10,000 Beats
Watch the hidden cutscene
Beat the game on Normal difficulty
Beat Catharsis in Normal difficulty
Beat Perception in Normal difficulty
Achieved a multiplier of 100 in Normal difficulty
Register a high score on the leaderboards
Beat Epiphany in Normal difficulty
Block all Beats during a Subtract Challenge
Escaped Nether Mode
Achieved a multiplier of 50 in Normal difficulty
Chained 200 Beats
Chained 100 Beats