Here is the full list of all 21 ALIEN XENOBLASTER achievements.
Beat Campaign!
Beat Campaign without using a single continue.
Beat every boss without taking damage at least once.
Beat Campaign on Hard Mode!
Beat Boss Rush!
Beat Boss Rush without using any continues.
Beat Boss Rush without taking any damage.
Beat Boss Rush on Hard Mode!
Survive 3 waves in Arcade Mode.
Survive 10 waves in Arcade Mode.
Score a PERFECT combo in Arcade.
Score 3 PERFECT combos in a row in Arcade.
Complete every challenge.
Switch a palette for the first time!
Beat World 1 in Campaign.
Beat World 2 in Campaign.
Beat World 3 in Campaign.
Beat World 4 in Campaign.
Beat World 5 in Campaign.
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