Complete the following tasks to unlock the corresponding achievement.
To view your achievements and stats in Steam, select "Community", then
"My profile", then "View all my games", then the game and view stats.
Achievement - How to unlock:
Academic - Finish Chapter II.
Aftermath-Inverter - Complete The Aftermath with 2 inversions.
Bridgewalker - Cross The Bridge.
Catcher - Catch the unchained key in The Courtyard.
Challenger - Finish Chapter IV.
Collector - Collect all hidden wisps.
Corridor-Inverter - Complete The Corridor with 3 inversions.
Garden-Inverter - Complete Mirrored Garden with 5 inversions.
Plummeter - Fall for 30 seconds.
Refrainer - Complete The Precipice without rotating.
Runner - Complete The Timepiece in less than 1 hour.
Scholar - Finish Chapter III.
Slider - Complete The Intersection without walking.
Thinker - Finish Chapter I.
Visionary - Complete all mirrored worlds.
Whisperer - Complete The Library being no louder than a whisper.