[HAS] Pestilence & Physic

Hearth & Sickle: Pestilence & Physic

Adds the Black Death, plague-carrying animals, cumulative exposure-based transmission, and medieval medicine to RimWorld, making quarantine, environmental management, and patient care essential challenges for your colony.

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What is the Black Death?

The Black Death is an infectious disease caused by Yersinia pestis. In the fourteenth century, it caused widespread epidemics across Eurasia and North Africa. It spreads mainly through infected fleas and animals, while pneumonic plague can also spread between people through respiratory droplets at close range. The mod represents three forms of the disease: bubonic, septicemic, and pneumonic plague. Plague-carrying animals, rat-flea exposure, respiratory transmission, and infestations encouraged by filthy environments recreate the risk of an outbreak. Disease progression and treatment effects are simplified for RimWorld gameplay.

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What can trigger a Black Death outbreak?

• Plague outbreak: Excessive garbage and rotting matter in the colony may attract animals carrying infected fleas. Colonists near these animals accumulate rat-flea exposure and may contract bubonic plague after reaching the infection threshold. • Person-to-person transmission: Active pneumonic plague patients cause respiratory exposure at close range. Prolonged contact raises the risk of infection and may eventually cause pneumonic plague directly. • Blood transmission: With the Biotech DLC enabled, a sanguophage who is not protected by an active perfect immunity gene and directly feeds on a confirmed Black Death patient immediately contracts septicemic plague, locked to that form. Vanilla sanguophages have perfect immunity by default, so they can only be infected through this route after the gene is removed or becomes inactive. Rat-flea and respiratory exposure accumulate over time. Once a pawn moves away from the source, the risk gradually subsides.

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What are the transmission ranges of plague carriers and Black Death patients?

• Plague-carrying animals: Cause rat-flea exposure within 4 tiles.
• Pneumonic plague patients: Cause respiratory exposure within 3 tiles. Patients with bubonic or septicemic plague do not spread the disease through close contact.

Solid walls and closed doors block exposure; open doors do not. Remaining within range causes risk to accumulate, while leaving the source allows it to gradually subside.

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Are treatments available?

Yes. The Black Death uses RimWorld's standard medical work and medicine system:

• Herbal medicine: Provides limited supportive treatment and only slightly slows disease progression.
• Industrial medicine and glitterworld medicine: Provide more effective treatment that significantly suppresses disease severity.
• Biosculpter pod: With the Ideology DLC enabled, a medic cycle has a chance to cure the Black Death.

Treatment does not directly increase the natural rate of immunity gain. Patients must still develop sufficient immunity before the disease becomes fatal, so medicine supplies, treatment quality, and continuous care all matter.

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Does the mod add its own medicines and crops?

Yes. The mod adds four medicinal crops and four medical products. Medicinal crops

• Opium Poppy: Produces raw opium, the main ingredient in dwale.
• Garden Angelica: Suited to cold climates and used to make herbal decoction.
• Cardamom: Grows in warm climates and can replace garden angelica in herbal decoction.
• Henbane: A dangerous, poisonous herb used to make dwale.

Medical products

• Herbal Decoction: Lasts about 6 hours, reduces pain by 15%, and slows rest loss.
• Barley Water: Provides a small amount of nutrition and slows hunger and rest loss for about 8 hours. Its recipe requires MedievalDiet.
• Recovery Caudle: Provides more nutrition, slightly reduces pain, and slows hunger and rest loss for about 12 hours.
• Dwale: Greatly reduces consciousness and movement after ingestion, quickly downing the pawn and halving pain. It is useful for restricting patient movement and assisting quarantine, but may cause vomiting and cannot replace proper surgical anesthesia.

These products mainly provide care, nutrition, or sedation. They cannot cure the Black Death directly. Downed pneumonic plague patients still infect people within 3 tiles, so they must remain in separate quarantine rooms.

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How can I keep disease out of my colony?

• Keep the colony clean: Promptly remove garbage, rotting matter, and animal corpses to prevent the environment from accumulating outbreak risk.
• Disable the mod options: Disable "Black death" in the mod settings to prevent new HAS Black Death outbreaks and plague carriers from spawning. Disable "Epidemic quests" to prevent new epidemic-related quests.

Disabling these options does not remove existing diseases, exposure, carrier states, quests, or sites. If an outbreak has already begun, treatment, quarantine, and environmental cleanup are still required.

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Can genes provide resistance to the Black Death?

Yes, but the effect depends on the gene, and only active genes provide protection.

• Perfect immunity: Prevents all new Black Death infections, including rat-flea, respiratory, and blood transmission. An existing Black Death infection is not removed immediately.
• Partial antitoxic lungs: Reduces respiratory exposure to 75%.
• Total antitoxic lungs: Reduces respiratory exposure to 50%.
• Breathless: Reduces respiratory exposure to 25%. Requires the Odyssey DLC.
• Tox resistance / tox immunity: Has no effect on the Black Death.
• Deathless: Does not prevent infection or disease progression. As long as the brain remains intact, vanilla mechanics cause the patient to enter deathrest or a regeneration coma instead of dying.

Genes that are overridden or otherwise inactive do not provide the protection described above.

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Can apparel provide protection?

Yes. Apparel provides protection based on its coverage, thickness, and degree of sealing.

• Rat-flea protection: Primarily provided by body-covering clothing, outerwear, armor, and vacsuits. It reduces rat-flea exposure caused by plague-carrying animals.
• Respiratory protection: Primarily provided by veils, masks, gas masks, full-head helmets, and vacsuit helmets. It reduces respiratory exposure caused by pneumonic plague patients.

The two protection types are calculated separately. When several effective apparel items are worn, protection of the same type stacks up to 80%, so the pawn always receives at least 20% of the exposure. Ordinary hats, blindfolds, collars, waist packs, and similar equipment that do not meaningfully cover the body or respiratory tract provide no protection. Protection values can be viewed in the information panels for apparel and pawns. Apparel only reduces newly gained exposure; it cannot remove accumulated exposure or treat an existing Black Death infection.

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Support and Feedback

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