Lore

You are a test subject sent to a gray planet for cargo. The three playable bodies are Sawians, artificial animals with designation numbers. That origin is in the in-game notes the wiki transcribes. The Observer's identity is not stated.

Sawians

The full write-up is on Sawians. Short version: SAW numbers, yellow blood, and a corporation experiment. Experiment is SAW-01, Milky is SAW-03, Dune is SAW-12.

Observer

A glitchy eye follows you, speaks the pause-menu lines, and closes in during last stand. The wiki confirms the behavior and says the identity is never stated. I am not equating it with Braingrow or with a separate entity some posts invent. Two sources would be required before I pick a name, and I have the wiki plus the same wiki's lore transcription, which are not independent.

Mindwipe

Mindwipe fluid, and a braingrow overdose, wipe memory, trauma, and recipes, set INT to 0, and apply Hollow. Some search results for mindwipe point at a comic on Reddit. I am not mixing that comic into the game mechanic.

Grey Planet is the place the notes send the subjects. I do not have a travelogue beyond the layer names and the lab at the surface, so I am not writing a chapter I have not read.