Here is the full list of all 26 BIT.TRIP Presents... Runner2: Future Legend of Rhythm Alien achievements.
Complete 50 Rewards
Unlock a New Character
Complete World 5
Get one Perfect+ in Each World
Complete World 4
Complete 40 Rewards
Run a Marathon
Complete World 3
Complete World 2
Checkpoints!? Who Needs 'Em!?
Complete 30 Rewards
Dance 100 Times
Complete World 1
Complete 20 Rewards
Complete 10 Rewards
Get a Bullseye
Complete 60 Rewards
Complete 70 Rewards
Complete 80 Rewards
Complete all 90 Rewards
Beat 30 Levels as Alternate Characters
Beat all Levels in Hard Difficulty
Get one Perfect Run in Each Level
Get a Triple Perfect+ on Every Level
Get two Double Perfects in Each World
Get three Triple Perfects in Each World