Here is the full list of all 12 Darker Skies: Remastered for PC achievements.
Complete the tutorial.
Complete the apartments.
Complete Nathan's Kingdom.
Complete Plane Wreckage.
Complete the prison.
Complete Castleton.
Complete the stadium.
Fully upgrade Jack.
Unlock all throwables.
Defeat the Fighting Machine.
Take out 3 enemies with a single throwable.
Repair the heatray and complete the game.