Here is the full list of all 44 Dark Old Sun achievements.
End the game in the normal difficulty in arcade mode.
End the game in the hard difficulty in arcade mode.
End the game in the Extreme difficulty in arcade mode.
End the game in the classic arcade mode.
End the game in the advanced arcade mode.
End the game in arcade, with classic mode using the Bullet Storm.
Defeat the first stage boss.
Defeat the second stage boss.
Defeat the third stage boss.
Defeat the fourth stage boss.
Defeat the fifith stage boss.
Defeat the sixth stage boss.
Shot more than 10.000 projectiles.
Shot more than 100.000 projectiles.
Deal more than 1k damage.
Deal more than 10k damage.
Deal more than 100k damage.
Get more than 50.000 crystals.
Get more than 250.000 crystals.
Get more than 500.000 crystals.
Survive for more than 2 waves in survivor mode.
Survive for more than 3 waves in survivor mode.
Survive for more than 4 waves in survivor mode.
Survive for more than 5 waves in survivor mode.
Survive for more than 6 waves in survivor mode.
Finish a challenge with at least a bronze medal.
Finish a challenge with at least a silver medal.
Finish a challenge with a gold medal.
Finish 5 challenges! with at least bronze medals
Finish 5 challenges! with at least silver medals.
Finish 5 challenges! with gold medals.
Finish 10 challenges! with at least bronze medals
Finish 10 challenges! with at least silver medals
Finish 10 challenges! with gold medals
Finish all challenges with at least bronze medals.
Finish all challenges with at least silver medals.
Finish all challenges with gold medals.
Clear stage 1 with full resistence bar in Arcade mode.
Clear stage 2 with full resistence bar in Arcade mode.
Clear stage 3 with full resistence bar in Arcade mode.
Clear stage 4 with full resistence bar in Arcade mode.
Clear stage 5 with full resistence bar in Arcade mode.
Clear stage 6 with full resistence bar in Arcade mode.