How the rat farm works
Raise rats in an Animal Cage, supply food directly or through a Livestock Feed Dispenser, and keep healthy males and females together to breed. Slaughter and butcher surplus rats for meat, then sell the meat while keeping enough food, space and repair materials for the remaining colony.
Rat Wrangler appeared in the earlier playtest and is listed among the starting scenarios for the full release planned for October 28, 2026. If that start is absent from your demo menu, use Joe Wild's Ranching route below.
Get live rats and an Animal Cage

Put cheese inside the trap before sleeping to improve the chance of catching a rat. The commissary sells cheese, but an unbaited trap can still catch rats.Playing this video connects to YouTube.
- Move your live rats into an Animal Cage. This is their housing and breeding space; prepare their food supply before leaving them overnight.
Load the feed dispenser before sleeping
- Place a Livestock Feed Dispenser inside the Animal Cage to feed from stored calories. Cage equipment such as the feed dispenser is allowed inside even though ordinary machines are excluded.
- Check the stored calorie level before sleeping or going out. Feeding is recurring upkeep, and running out can cost you the litter; keep a reserve before expanding the colony.
Breed healthy rats and select useful traits

A male and female sharing suitable housing can breed. Check for the Mature tag before expecting pregnancy: the breeding guide shows rats becoming eligible at 3 days old. Pregnancy is chance-based, with the pair's lower Fertility value determining the chance.Playing this video connects to YouTube.

Use the Gene Scanner's toggle to reveal the deeper trait readout. Compare growth, litter size, immunity, health, longevity, hunger and fertility when choosing breeding animals. For Hunger Rate, lower is favorable: the demo's corrected tooltip shows low rolls in green and high rolls in red.Playing this video connects to YouTube.
Keep breeding within the food and housing you can maintain. A Wire Cutter can neuter rats to prevent unwanted breeding, giving you a way to control expansion rather than continually adding mouths to feed.
Clean, expand and repair the cage
Cage wear scales with the size of the living animals inside. Dead animals, cage equipment and other stored items cause no wear, so a growing colony needs attention even when its head count stays unchanged.

Use a metal ingot on the Animal Cage to expand its space. Each ingot size upgrade also adds 20 maximum durability and 20 current durability.Playing this video connects to YouTube.
Prevent disease and food shortages
Keep rat meat out of the colony's food supply. Feeding it back to rats risks Prion Disease, which harms immunity, growth and longevity. The demo has no cure, so keep harvested meat separate from food intended for the dispenser.
Disease lowers fertility and meat output, making sick animals costly for both breeding and harvesting. Immunity Serum boosts immunity, while growth or steroid serum increases growth at the cost of immunity; consider that trade-off before treating valuable breeding stock.
Harvest meat and turn it into sales
- Choose a surplus rat for harvesting after checking its weight and health. Weight determines meat output, and disease reduces the yield, so compare the animal's condition with the food and space needed to keep raising it.

Equip a suitable knife or meat cleaver to prepare for slaughter. A sharp harvesting tool is required to turn the rat into meat.Playing this video connects to YouTube.

Use the equipped blade on the selected live rat to slaughter it. Keep your chosen breeding animals separate while carrying out this action.Playing this video connects to YouTube.

Harvest the dead rat with the blade to obtain its meat. The commercial output is the meat, rather than treating live rats as ordinary retail stock.Playing this video connects to YouTube.
Budget for automation as well as food and repairs. Upgrading the Vacuum Robot with a Common Electronic enables an incinerator that destroys collected feces after cleanup, but running it doubles the robot's normal power use.