Here is the full list of all 12 Into The Gloom achievements.
Embrace the agony for the rest of eternity.
Achieve the ultimate goal.
Experience the existence as a lesser life form.
Disappear forever...
Become a homeless.
Find all the main menu unlockable notes.
Escape the lonely underground maze.
Meet the box of salvation.
Free the knife dude from the prison yard.
Visit your home again.
Fail to achieve the ultimate goal.
Arrive to the red plane.