Here is the full list of all 25 Danmaku Unlimited 2 achievements.
Defeat the True Boss.
Collect one trillion points.
Beat the game with no weapon upgrades.
Reach the rank of Ace.
Reach the rank of Wing Commander.
Reach the rank of Major.
Reach the rank of Colonel.
Reach the rank of Squadron Captain.
Beat stage 5 in Classic Mode.
Complete the game in Classic Mode.
Collect one billion points.
Beat stage 4 in Classic Mode.
Beat stage 3 in Classic Mode.
Beat stage 2 in Classic Mode.
Beat stage 1 in Classic Mode.
Beat stage 5 in Burst Mode.
Complete the game in Burst Mode.
Collect 100 million points.
Reach the rank of Flight Lieutenant.
Reach of rank of Sergeant.
Reach the rank of Master Sergeant.
Beat stage 4 in Burst Mode.
Beat stage 3 in Burst Mode.
Beat stage 2 in Burst Mode.
Beat stage 1 in Burst Mode.