copied, from my Astats Guide for this achievement
This achievement requires you to go through the whole game and jump into the portal in Acceptance on a new save without dying
Stages that require you to beat to get this achievement:
The end
Arid flats
Overflow
Wall of sorrow
SS exodus
The hollows
Golgotha
Retrograde
The machine
The Future
Anguish
Gloom
Blight
Ruin
Acceptance
Note: You do not need to finish Nevermore, only up untill You finish Acceptance when the credits start rolling, you also dont need to get all the cartridges and tumors
You also dont need to finish all cartridges