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