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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
Work Speed Stat
Research Speed

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. The gene packs are not consumed. 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 Capsules archite 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 have a minimum metabolic efficiency of -5. Pawns cannot receive xenogerms that would lower their efficiency below this value.

Xenogerms completely overwrite a pawn's xenogenes, genes which are not passed down through reproduction. This will outright remove xenotypes that are defined by xenogenes, such as genies or sanguophages. Xenotypes using germline genes, such as impids, will not have those genes removed. However, germline genes will be suppressed if they would conflict with the xenogerm. For example, a Fast Runner xenogerm will completely suppress a Slow Runner germline gene.

Multiple xenogerms can be implanted on the same pawn, though each one overwrites the last. This includes archite genes, which effectively means that any archite capsules previously spent on the pawn will be lost.


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.

Breakdown of Xenogermination Time[edit]

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
  • Analysis[edit]

    The use of a xenogerm depends on what genes are contained within it, used to counter unfavorable genes from the germline such as weak melee damage on a Impid with a passion in melee, as a medical tool in the event of life-threatening illness with Strong Immunity. When making a xenotype with hybrids or children ideally it should be applied within the infancy stage as the pawn cannot work or learn regardless, and the coma will be the least impactful.

    For purifying genepacks into just 1 or 2 genes, a xenogerm can be applied to a baseliner prisoner or any other undesirable pawn to kill them later with a Gene extractor and attempt to acquire a genepack with the desirable genes.

    Xenogerms also satisfy Body Modders. Transhumanists Content added by the Ideology DLC and subsequently disgust Body Purists and Flesh Purists,Content added by the Ideology DLC Purely cosmetic genes can be inserted into a Body Modder for a free +4 mood with no impact compared to other options like Dentures

    The only way to remove a xenogerm is to kill the pawn with a Gene extractor and resurrect them.

    Xenogermination coma can technically be healed by a healer mech serum, but the item is too rare for this to be practical. However, if a colonist with the mostly-equivalent unnatural healingContent added by the Anomaly DLC ability is available (and tentacle limbs are not undesirable), there is little reason not to use it to instantly wake an important pawn.

    Version history[edit]

    • Biotech DLC Release - Added
    • 1.4.3534 - Fix: Pawns will continue to create a xenogerm until they pass out.
    • 1.4.3613 - Fix: Xenogerms with different genes and name stack in trade screen.