Here is the full list of all 15 Beatbuddy: Tale of the Guardians achievements.
Complete level 1
Collect a total of 2000 Beatpoints
Destroy 200 containers
Jump through Snarestreams 100 times
Accomplish 20 Rhythm Combo's
Defeat 100 Soldiers
Complete the Elite Training in the Camp
Defeat the captured Parasites in level 4 without getting hit
Unlock all the Extras
Complete the game in under 3 hours
Complete level 2
Complete level 3
Complete level 4
Complete level 5
Complete level 6