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