The Machine

The Machine is an unknown entity referred to by the name "The Machine" and by the nickname "the Headless Raven". The aforementioned nickname is given because "it spits out raven's heads." The Machine is referred to as a kind of "underground god", and is said to have been created by Andrew Herts, who was helped by seven masked men (likely from the Underground City.) These masked men guarded the project, and seeked the ingredients, especially poor people (homeless). These "poor people" are referred to as "a gift from the upper bird". It runs on five ingredients: sand, rocks, water, ornis (birds) and humans (homeless).

A note stating this information is found on a note located in a small foliage-covered cave hidden behind the Pine Fell Water Plant in tunnel2.

In Bunker, there is a computer displaying encrypted text, which, when decoded, produces part of the text "Homeless People (made the) machine". However, this information contradicts the information in the note, which states that the machine was made by Andrew Herts. A possible explanation is that the machine was actually made of homeless people. This could coincide with the mushrooms/blue mushrooms (aka "ugu shrooms"), possibly mutating the said people and assimilating them into The Machine.

The text on the computer reads: "UGU is the underground world god. Masked man in the tunnel guards the knowledge. Raven Research Institute is the lead organization. Inventor is Andrew Herts, homeless people made up The Machine."

The note as it appears in-game:

The same note, cleaned up for visibility purposes:

The note reads:

Andrew Herts made the machine
that became a legend in Stalburg-
a creature, once known as the
god of the underground. The
machine runs on five ingredients:
sand, rocks, water, ornis, and (humans?)
Herts made the machine because
he claims to "save the poor people".
The machine is called the Headless
Raven because it spits out raven's
heads.
Herts is helped by seven masked
men. They guard the project and
seek ingredients, especially poor
people. They're a gift from the
upper (bed?)

("ornis" means "bird").

Feel free to investigate!