Here is the full list of all 20 BATSUGUN Saturn Tribute Boosted achievements.
Complete Round 3 (Special Ver.).
Complete Round 2 (Special Ver.).
Earn 1,000,000 points with secret pigs.
Fill one experience gauge up with purple secret pigs.
Complete Round 1 (Special Ver.).
Complete Stage 5.
Complete Stage 4.
Complete Stage 3.
Increase your level to 3.
Complete Stage 2.
Increase your level to 2.
Complete Stage 1.
Don't let a plane take off in Stage 2.
Complete Round 4 (Special Ver.).
Collect 100 small Vs in a stage.
Collect 50 big Vs in a stage.
In the original version, make a score of 1,000,000 points.
In the original version, make a score of 2,000,000 points.
In the special version, make a score of 5,000,000 points.
In the special version, make a score of 10,000,000 points.