Here is the full list of all 25 BEAT ARENA achievements.
Complete campaign 1 to 5.
Complete 30 sessions in the campaigns for total.
Complete the all campaigns.
Play guitar for 20 times for total.
Play guitar for 50 times for total.
Play guitar for 100 times for total.
Play drums for 20 times for total.
Play drums for 50 times for total.
Play drums for 100 times for total.
Play bass for 20 times for total.
Play bass for 50 times for total.
Play bass for 100 times for total.
Play keyboard for 20 times for total.
Play keyboard for 50 times for total.
Play keyboard for 100 times for total.
Upload playdata for the first time.
Upload playdata for 50 times.
Play a session with another player's playdata for the first time.
Follow another player for the first time.
Watch own playdata for all instruments.
Watch other players playdata for all instruments.
Reach a score of 1000000 for the first time on difficulty level Casual.
Reach a score of 1000000 for the first time on difficulty level Advanced.
Reach a total score of 100000000 for each difficulty level.
Successfully enter Konami command.