The Sub-Basement

rating: +14

18 votes (+16, -2) 4.4★

rating: +14+x

Level Classification

Difficulty 3/5 Rock bursts, drafts of air, and heat that can boil people alive make this level difficult to traverse.
Entity Count 1/5 Entity encounters are rare.
Chaos Gradient 1/5 The environment is relatively stable, with occasional rockburst and tunnel collapse.
Basset-Frazier Index 1.667/5 This level is anomalous, even more so than previous quantum stable levels.



fig 1.0 The Sub-Basement

The Sub-Basement is a continuously expanding subterranean complex filled with pipes and machinery. Passages are circular and bored from solid rock, with a layer of gravel covering the ground and pipes running along the walls. Large vertical mineshafts punctuate the level, housing active boring machines at their bases and extending upwards to incalculable heights. The upper reaches of the level are filled with dead and inoperable machinery with sparse to nonexistent lighting, while in the newer, more dangerous tunnels closer to the bottom of the level active machines can be found.

Deeply buried machinery transports and processes crushed stone extracted from the depths and shield against the intense heat radiating from below. In the very lowest regions of the level active boring machines can be found, continuing to drill through the superheated rock to expand the machinery ever deeper into the level. While the cooling systems maintain a sweltering but survivable air temperature in even the deepest of tunnels, the temperature of the walls, machinery, and even gravel floor becomes increasingly dangerous with depth. Explosive rockbursts from the walls under tremendous stress are a low but constant risk throughout the level, made exponentially worse by any attempts at digging.

The vast Von-Neumann machine of The Sub-Basement seems to be partitioned into a repeating grid of discrete, cubic-kilometer mechanical "cells", each of which act as a complete machine unit capable of independent function and self-replication in a manner analogous to biological cells. These cells are categorized according to type, as expanded upon below.

Dead Cells

The machine cells farthest from the layer of active expansion are categorized as dead cells, having shut down all active functions after successfully self-replicating into the layer below. Temperatures range from slightly above room temperature to frigid, as these cells support the cooling system which keeps the active cells in the habitable temperature range. It is in this region of the level that iron ladders are a safe method of entering lower tunnels, as temperatures are low enough at this height to allow safe contact with metal surfaces. Deeper into the level it is recommended to find and descend a spiral tunnel if possible when ladders become unusable.

Lights are frequently non-functional, with the very highest of explored dead cells even being deprived of power. Such far cells have grown so distant from the mining front that they have entirely ceased to serve any function in the greater machine of the level, even as cooling systems. Collapsed sections are common, as in these derelict areas the level does not seem to bother repairing itself. The most prominent feature one may find in these cells are vast vertical mineshafts lined with rails where the processing machinery was lowered into younger cells below. While these shafts pose one of the few dangers in the dead cells — that of falling — they also provide a quick route down to the processing cells, if one is not adverse to climbing.

Processing Cells

In processing cells, the vertical mineshafts are occupied by towering structures of layered platforms secured to the rails containing cities' worth of automated machinery specializing in smelting, forging, and manufacturing, forming the true heart of the The Sub-Basement machine complex. The tunnels house a network of conveyors, pipes, and conduits which tie the processing plants into the level, supplying them with power and materials from below and transporting the manufactured parts down to the cells undergoing active construction. Temperature becomes a noticeable problem, with walls burning at the touch like hot pavement, and the air becoming stiflingly hot. The sound and smell of machinery is constant, echoing down every passage in a continuous roar of thunderous booms and sulfurous fumes.

Equipment can also be found here, in lockers nested within the webs of machinery, frequently containing hard hats, plexiglass face shields, earplugs, thick leather gloves, knee pads, and steel-toed shoes. Rarely tools such as pickaxes, crowbars, wrenches, and even welding equipment can be found in these lockers, which are useful as weapons but should not be used in any attempts to tamper with the machinery, which usually result in violent deaths.

Active Cells

In the very lowest of cells the machines are still actively boring the tunnels out from the rock, and in many places the cooling systems are not yet in place. The most notable features of this layer are the boring machines, continuously drilling into the rock, digging out tunnels through which to grow new machine cells. At the bottom of the vertical mineshafts are found large vertical drills known as tusks, and at the ends of branching tunnels are horizontal boring machines known as molars. Raw materials from The Lithostructure are continuously extracted, being transported up to processing cells for refinement. These materials are either used to manufacture new parts to be returned to the active cells for use or simply disappear on strange dead-end conveyors, for purposes unknown.

The atmosphere in these cells is incredibly hot, to the point of heat stroke under long term exposure. Worse, steam leaks from the boring machines saturate the air with moisture, making the heat even more unbearable. The constant rumbling of machinery is incredibly loud at this depth, although mostly in the subsonic range what can be heard is deafening and earplugs from the the layer above are definitely recommended. Walls will burn on contact and the coolant pipes reach into the temperature range of liquid nitrogen, making touching them equally unadvisable.

The exits are notably located in this layer, behind iron service doors built into the tops of the tusk drilling devices. These doors are notably quite hot like the rest of the machine, and should not be opened with bare hands. If gloves cannot be found, an item of clothing such as a shirt can be removed and wadded about the hands as improvised insulation. One should remain in this layer for only the amount of time it takes to locate an exit and leave.


Due to the difficulty of this level, permanent civilizations are unfeasible and impossible to sustain for lengthy periods of time.



The Sub-Basement can be entered by going down hatches in The Basement or by entering a "Staff Only" door in Boundless Retail.


Service doors within the tusk drills at the bottom of the vertical mineshafts lead to Electrical Station.
It is also possible to climb back up through a hatch to return to The Basement.

More Levels:

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The Halls - (+52)

The Basement - (+27)

Your Home - (+15)

The School - (+17)

The Aquarium - (+21)

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