Quick answer

If Prion Disease keeps returning, check the food in the feeder before replacing the colony. Players in the September 29 disease discussion link outbreaks to feeding rats food made from rats, and recommend emptying that feed supply. High immunity alone is not a reliable reason to ignore the food.

For Gene Scanner controls, players report that you must activate the scanner, then hover over a rat to see its additional genetic details. These feeding and scanner instructions come from player reports; they have not been independently tested for this guide.

This page covers the Steam Demo's UPDATE 049 cage changes and dated player reports. The earlier Rat Wrangler Playtest start does not establish which starts are selectable in your Demo.

Prion disease: what to check first

The disease discussion describes an outbreak that returned even after the player removed the original rats. Other players point to the feeder's remaining contents as the problem. Their troubleshooting approach is:

  1. Check whether rat meat or other food made from rats went into the feeder.
  2. Empty that food supply rather than leaving it available to a replacement colony.
  3. Use food from another source and watch for further cases.

This is a reported way to remove a suspected exposure source, not a demonstrated cure for an already infected rat. The discussion and a later genetics post distinguish ordinary illness from Prion Disease. Do not assume an immunity value that helps with ordinary illness also prevents prion exposure.

No confirmed medicine, cure, or guaranteed recovery time is available in the sources linked here.

How to use the Gene Scanner

In the Gene Scanner discussion, replies describe activating its in-game toggle and hovering over the rat. Buying it and leaving it inactive is not the same as scanning.

Breeding players use the extra information to compare potential parents, rather than judging them only by the headline stat. The official UPDATE 049 notes also corrected the scanner's Hunger Rate colors: a lower roll displays green and a higher roll displays red.

If you mainly raise rats for meat and are short on money, the sources do not establish that a scanner is mandatory for a profitable colony.

Which genetics should you prioritize?

The October 3 breeding post recommends balancing growth, hunger, immunity, litter size, health, and longevity. It describes selecting better offspring and periodically replacing breeding parents.

That post combines the author's play observations with claimed game-data analysis. Its exact mutation rates, immunity thresholds, growth formulas, and income estimates are not verified here. Treat them as hypotheses rather than fixed limits for every Demo build.

A practical comparison is to record the parents' displayed traits, scan details, and offspring results before changing several traits at once. A rat with faster growth may still cost more to feed or leave you with a less resilient colony.

Animal Cage durability and repairs

The developer's September 14 UPDATE 049 notes confirm these changes:

  • Wear scales with the size of living animals inside. Dead animals, cage equipment, and other stored items cause no wear.
  • Each ingot size upgrade adds 20 maximum durability and 20 current durability.
  • Scrap repairs restore 50% of maximum durability, replacing the earlier flat repair amount.
  • Machines cannot be placed inside, except cage equipment such as the Vacuum Robot and feed dispenser.

Check cage durability alongside food and health. Adding animals without room and maintenance can turn a larger colony into more work rather than more income.

Catching and processing rats

The earlier “What to do with rats?” discussion describes traps, separate storage, and using a knife to process rats into meat. These are player-reported actions from the Playtest period. Check the available actions in your Demo before planning a production loop around them.

For the difference between earlier starts and the Demo, see starting scenarios.

Sources

Sources checked October 4, 2026. No current game build was independently tested.