Here is the full list of all 39 Nex Machina achievements.
Complete all achievements
Complete 100 feats
Complete Techno Forest on Master difficulty
Complete Arcade mode on Veteran difficulty
Complete 50 feats
Beat Machine City on Experienced difficulty in under 5:45
Earn 9 gold medals in the Arena
Earn 6 silver medals in the Arena
Earn 3 bronze medals in the Arena
Complete Arcade mode on Experienced difficulty
Complete Arcade mode on Experienced difficulty without continuing
Complete Space Station in arcade mode on any difficulty
Reach a human combo of 50
Save all Humans and Secret Humans in a single world on Veteran difficulty
Save all Secret Humans in a single world on Experienced difficulty or higher
Complete a single world on Experienced difficulty without saving any humans
Clear a single world on Experienced difficulty or higher without getting hit
Deal a killing blow to a boss with a Sword attack
Dash through 3 beams with single dash
Defeat the Beamtron on Experienced difficulty with one or more enemies still alive
Clear a single world while succeeding in every end-level minigame on any difficulty
Succeed in 10 end-level minigames in a row on any difficulty
Destroy every Secret Beacon in a single world
Discover a secret level
Finish 5 levels in a row without movement, dashing allowed
Finish a level without firing your primary or your secondary weapon
Complete Future Labs in arcade mode on any difficulty
Complete Arcade mode on Rookie difficulty
Reach a multiplier of 50
Complete Machine City in arcade mode on any difficulty
Complete Fire Caverns in arcade mode on any difficulty
Complete Crystal Mountain in arcade mode on any difficulty
Kill every Disruptor in a single world
Complete Techno Forest in arcade mode on any difficulty
Complete a feat
Fully power up the Hero
Kill a Disruptor
Reach a human combo of 5
Save a human while it's being harvested