Here is the full list of all 13 Parallax achievements.
Complete Chapter D
Complete every level using no more than the required number of actions.
Spin around 360 degrees, travel 5 meters, cross a rift, and die by lasers, without touching the ground or using a booster.
There is no escape.
Does whatever a spider pig does.
Complete Chapter C
That was close!
Use a terminal 300 times.
Travel between light and dark 500 times.
Complete Chapter B
Die 20 times.
I don't remember what happened.
Complete Chapter A