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A self-contained biological organ containing one or more implantable xenogenes.

Once implanted inside a host's body, the xenogerm modifies the host's genes, gene expression, and phenotypic development using viruses, hormones, bio-synthesized drugs, and possibly mechanites. Depending on the xenogerm, the host will develop any of a wide variety of exotic traits and abilities, transforming them into a different human xenotype.

Xenogerm implantation is a traumatic process. Once implanted with a xenogerm, a person will be bedridden for days as the transformation sets in.

During storage and transport, xenogerms are kept safe in sealed containers.

Base Stats

Medical ItemsBody Parts
Tech Level
Market Value
100 Silver


Crafted At
Gene assembler
Required Research
Skill Required

A xenogerm is a specialized organ used to change the xenotype of a pawn.


Xenogerms are created at a gene assembler by combining the genes from genepacks stored in nearby gene banks. Creating a xenogerm is considered a form of research, and requires the intellectual skill. The actual time to create a xenogerm depends on the genetic complexity of the genes it contains—ranging from 4 hours at 3 or less complexity, to 23 hours at 20 or more complexity—and then this is scaled by the worker's research speed.

Normally, xenogerms can be created for free. However, if they contain any archite genes, then the required number of Archite Capsulesarchite capsules will need to be provided before gene recombination can begin.


The purpose of a xenogerm is to change the xenotype of the pawn it is installed into. This is done through an implantation surgery. The effects of xenogermination are instant, and will change the affected pawn upon the surgery's completion.

Xenogerms require a minimum metabolic efficiency of -5. Pawns cannot receive xenogerms that would lower their efficiency below this value.

Xenogerms can only add xenogenes to a pawn, meaning that their effects will not be inherited by children.

Gizmo xenogerm order implantation.png

Since each xenogerm is unique, its implantation must be ordered manually. There are three ways to do this:

  • Select the xenogerm. Click on the "Order implantation" gizmo. Select the desired patient from the list.
  • Select your patient. Right-click the xenogerm, then click "Order implantation".
  • Select your patient. Open their health tab, then view their queued surgeries. Select "Add bill", then choose "Implant xenogerm". Choose the desired xenogerm from the list that appears.

Once the bill is ready, a doctor will need to perform the implantation surgery. The operation requires 4 medicine of herbal quality or higher, and requires 2,000 ticks (33.33 secs) of work.

After implantation is complete, the patient will enter a "xenogermination coma". This lasts about 2 days, depending on the quality of the surgery, and will cause a total inability to move. See the section below on more details on how this time is calculated.

In addition, the patient's genes will need between 6,000,000 ticks (1.67 years) and 8,400,000 ticks (2.33 years) to regrow. Extracting their genes with a gene extractor during this time will kill them. However, it is safe to implant another xenogerm during this time.

Multiple xenogerms can be implanted into the same pawn. However, each new xenogerm will overwrite the effects of the last. In other words, if the pawn has xenogenes not contained in the new xenogerm, then they will always be removed. This includes archite genes, which effectively means that any archite capsules previously spent on the pawn will be destroyed entirely.

Breakdown of Xenogermination Time

There are a number of factors and specific effects on xenogermination time, which the list below will break down.

  • Click to
    • The time spent in a xenogermination coma depends on the quality of the surgery, clamped within 0% and 100%
      • At 0% quality, the duration will be 3 days
      • At 100% quality, the duration will be 1 day
      • This means that the duration in days can be found with the equation: 3 - (Quality × 2)
    • The quality of the surgery depends on the following factors:
      • The surgery has a base quality of 100%
      • Multiplied by the medical surgery success chance of the surgeon.
      • Multiplied by the surgery success chance factor of the patient's bed.
      • Doubled if the doctor has an inspired surgery
      • Multiplied by the medical potency of the medicine used, based on a simple curve.
      • Multiplied based on the overall complexity of the xenogerm
        • Factor starts at 100% at 0 complexity
        • -2% for each point of complexity
        • Minimum factor of 60%, at 20 points of complexity
      • Multiplied based on patient's age
        • 100% up to age 20
        • -1.25% for each year after 20
        • Minimum of 50% at the age of 60
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