Here is the full list of all 21 BIT.TRIP CORE achievements.
Beat the game in one sitting without getting a Game Over
Blast 10,000 Beats
Play through one entire stage in Super Mode in Normal difficulty
Chained 200 Beats
Watched the hidden cutscene
Chained 100 Beats
Register a high score on the leaderboards
Escaped Nether Mode
Get a PERFECT score in Discovery
Get a PERFECT score in Exploration
Get a PERFECT score in Control
Achieved a multiplier of 50 in Normal difficulty
Achieved a multiplier of 100 in Normal difficulty
Chained 500 Beats
Beat Discovery in Normal difficulty
Beat Exploration in Normal difficulty
Beat Control in Normal difficulty
Blast all Beats during a Challenge
Beat any level without using a Bomb in Normal difficulty
Blast 30+ Beats at once with one Bomb
Beat the game on Normal difficulty