Among the many biological horrors infesting the Deepwell Facility, few are as common—or as feared—as the Wellleeches.
They are rarely noticed until it is too late.
They do not roar, stalk, or charge like predators.
They simply attach.
Researchers from the Advanced Scientific Authority and Advocacy Group originally dismissed them as simple parasitic organisms. That conclusion was abandoned after several expeditions returned with survivors whose bodies contained dozens of leeches that had fused permanently with their nervous systems.
The creatures are now classified as cognitively invasive parasites.
A Wellleech resembles a long, pallid leech roughly the size of a human forearm, though older specimens can reach over a meter in length.
Their skin is semi-translucent and oily, revealing slow-moving black fluids pulsing through segmented channels along their bodies. The surface is covered in tiny barbed cilia that allow them to crawl silently along metal walls, pipes, and ceilings.
Their mouths are not circular like natural leeches.
Instead, they open into triangular, iris-like flaps lined with dozens of retractable bone needles. When feeding, these needles extend into flesh like surgical probes.
Their rear segments split into branching tendrils that anchor into surfaces, allowing them to hang upside down like dripping cords of flesh.
Under dim light, the creatures appear wet and reflective, making them difficult to notice against the dark industrial surfaces of the Facility.
Wellleeches thrive in the moist maintenance systems of the Deepwell Facility:
Condensation channels
Cooling pipe clusters
Wastewater drains
Oxygen filtration chambers
They often gather in large colonies, hiding in pipe bundles where dripping fluids create warm environments.
When the Facility’s air circulation activates, they sometimes fall from overhead vents like living rain.
Unlike ordinary parasites, Wellleeches do not primarily consume blood.
They feed on neural signals.
Once attached to a host, the creature inserts its needle-like proboscis into the spine or base of the skull. From there it begins siphoning electrochemical signals from the nervous system.
Victims experience:
Sudden memory loss
Muscle spasms or paralysis
Hearing faint whispers or static
Loss of control over certain movements
During feeding, the leech’s body swells as its internal channels glow faintly with electrical pulses stolen from the host’s nervous system.
The creature essentially drinks thoughts.
If a Wellleech feeds long enough, it begins to stimulate the host’s nervous system directly.
Victims may unknowingly walk deeper into the Facility while partially controlled by the parasite.
Entire expeditions have been lost this way.
When multiple leeches attach to a host, they may coordinate movement, turning the victim into a puppet-like carrier that spreads the parasites further into unexplored sections.
In extreme cases the body continues walking days after brain death, animated by twitching clusters of feeding leeches.
Wellleeches reproduce through a disturbing process known as neural budding.
After consuming enough neural energy, a mature leech splits along its body, forming several smaller offspring. These offspring retain fragments of the neural patterns they absorbed from hosts.
As a result, some young Wellleeches exhibit disturbingly human-like movement patterns, crawling in jerky motions that resemble fingers grasping or hands dragging across surfaces.
Signs that Wellleeches inhabit an area include:
Wet streaks of oily residue along pipes
Small twitching shapes in condensation puddles
Quiet tapping sounds inside ventilation ducts
Corpses with thin black cords trailing from the spine
Inmates report that large colonies produce a faint sound resembling static mixed with distant breathing.
Some believe this noise is the combined electrical signals stolen from dozens of victims.
ASAAG researchers suspect the Wellleeches did not originate from any known ecosystem.
Their nervous-system feeding mechanism appears too precise, suggesting they evolved—or were engineered—to interact with intelligent organisms.
Some scientists speculate they may be biological data collectors, harvesting neural patterns from intruders for some unknown intelligence embedded within the Deepwell Facility.
A single rule circulates among long-term survivors:
If something wet falls from the ceiling—do not brush it away.
Because by the time you feel it…
it has already found your spine.