Four distinct systems of cat afflictions — what hurts, what helps, what's permanent, and what you can cure. Knowing the difference between a disease and a disorder can save your run.
Mewgenics has four completely separate affliction systems. Each has different triggers, durations, effects, and removal methods. Understanding which system you're dealing with is the first step to managing it.
| System | Permanent? | Max Stack | Removal | Primary Cause |
|---|---|---|---|---|
| Diseases | No (curable) | Unlimited | Rest nodes, items, high room health | Low room health, combat, events |
| Disorders | Yes | 2 per cat | None (permanent) | Events, low CON, trauma |
| Birth Defects | Yes | Varies | None (permanent) | Inbreeding, high coefficient |
| Parasites | No (removable) | 1 per item slot | Dr. Beanies (Butch currency) | Low room health, dirty environments |
Diseases are the most common affliction type. They are curable and directly tied to your House's room health stat. A clean, well-maintained House produces cats that resist diseases. Dirty rooms produce sick cats.
Diseases apply stat penalties, ability lockouts, or combat debuffs. They are removed by:
| Disease | Stat Penalty | Effect | Cure Method |
|---|---|---|---|
| Snuffles | -1 CON | Reduced max HP; cough animation during combat | Rest, Cure item |
| Mange | -1 CHA | Reduced Social event success; visual fur loss | Rest, Cure item, high health room |
| Glow Sickness | -1 INT, -1 CON | Occasional confusion in combat; reduces mana gain | Cure item, Purify ability |
| Rotting Wound | -1 STR, -1 DEX | Damage over time between nodes; risk of sepsis | Cure item, Rest if high CON |
| Fever | -1 all stats | Global stat penalty; weakens entire run performance | Rest, Cure item, multiple rests may be needed |
| Lethargy | -1 SPD | Acts last in turn order; reduced dodge chance | Rest, Cure item |
Each room in your House has a hidden health stat. Low health triggers disease checks when cats are bred or housed there. Invest in furniture that boosts room health (clean bedding, ventilation items) to reduce disease rates. A room with 60+ health effectively eliminates disease risk for cats in that room.
Disorders are permanent conditions that modify a cat's stats and behavior. The cap is 2 per cat — a third disorder cannot be applied to a cat that already has 2. Unlike birth defects, some disorders have meaningful positive effects that advanced players deliberately breed for.
Cats can have a maximum of 2 disorders. A cat that already has 2 cannot gain a third — the new disorder is rejected. This can be used strategically: deliberately give a cat 2 minor disorders to block worse ones from stacking up over a long run.
| Disorder | Type | Effect | Breeding Value |
|---|---|---|---|
| Autism | Mental | -2 mana cost to the cat's starting spell (the first ability in slot 1) | High — Breed For |
| Leprosy | Physical | Drops 4 HP food items every time the cat takes damage — functionally equivalent to 4 Brace | High — Sustain Build |
| Depression | Mental | -2 melee damage taken by this cat; subtracts 8 max HP from all adjacent units (allies and enemies) | Situational |
| Williams Syndrome | Mental | Basic attacks apply the Charm status to hit targets | Control Build |
| ADHD | Mental | Dual-natured — erratic behavior with both speed boosts and misfires | Avoid |
| Insomnia | Mental | Dual-natured — impaired rest healing and unpredictable stat swings | Avoid |
| Psychosis | Mental | +1 to all stats but causes Madness after Turn 1 — the cat may turn on allies | Dangerous |
| Crohn's Disease | Physical | Dual-natured — digestive disruption affecting food item effectiveness and stamina | Avoid |
| Gastritis | Physical | Dual-natured — reduces healing from food items but may provide combat bonuses | Avoid |
The most powerful disorder breeding combination is Autism linked with the Chosen Warrior Grey skill. Autism reduces the starting spell's mana cost by 2; Chosen Warrior is a game-breaking ability. Together they create a cat with maximum ability power at minimum mana cost — the target build for Impossible difficulty runs. See the Genetics page for Grey skill farming methods.
Birth defects are permanent physical deformities caused by inbreeding during breeding. They manifest when the parents' genetic kinship coefficient is too high. Unlike disorders, birth defects have no positive aspect — they are strictly detrimental. They cannot be removed by any means.
Birth defects are the direct consequence of breeding related cats. As the inbreeding coefficient rises above 0.3, defect risk accelerates sharply. Above 0.7, almost every kitten will have at least one defect. The only way to avoid them is to introduce unrelated stray cats into your breeding pool. Inbreeding also reduces stat caps on offspring, compounding the penalty over generations.
| Birth Defect | Effect | Stat Impact | Inbreeding Coefficient Trigger |
|---|---|---|---|
| Missing Eye | -1 DEX; reduced crit chance | -1 DEX | 0.15+ |
| Club Foot | -1 SPD; reduced movement range in combat | -1 SPD | 0.2+ |
| Deformed Spine | -1 CON; reduced max HP | -1 CON | 0.3+ |
| Stunted Growth | -1 STR; reduced carry capacity | -1 STR | 0.4+ |
| Hydrocephalus | -1 INT; occasional stun in combat | -1 INT | 0.5+ |
| Fused Digits | -1 DEX; cannot equip gloves | -1 DEX, slot block | 0.6+ |
| Blindness | -2 DEX; misses often; can't scout | -2 DEX | 0.7+ |
| Deafness | -1 all stats; can't respond to commands | -1 all | 0.8+ |
| Inbreeding Coefficient | Birth Defect Risk | Body Defect Risk |
|---|---|---|
| 0.0 (Unrelated) | 2% (baseline) | 0% |
| 0.05 | ~2% | 0% |
| 0.15 | ~4% | 15% |
| 0.3 | ~10% | 45% |
| 0.5 | 14% | 75% |
| 0.7 | 22% | ~90% |
| 1.0 | 34% | ~95% |
| 1.2+ | 42% (cap) | ~100% |
Always keep a pool of unrelated stray cats in your House. Breed your best cats with strays every 2-3 generations to reset the inbreeding coefficient. Tink's genetics display (after 40 donated kittens) shows you the exact coefficient so you can plan precisely when to introduce fresh blood.
Parasites are external organisms that attach to a cat and occupy an item slot. They are not permanent — they can be removed — but while active they reduce stats, drain resources, and prevent you from equipping gear in the affected slot.
Parasites are removed by Dr. Beanies, a meta-progression vendor accessible through Butch in the House. Dr. Beanies accepts donated cats as currency. Each parasite removal costs a specific number of cat donations. Running low on donation cats means your party carries parasites until you breed more.
| Parasite | Slot Blocked | Effect | Dr. Beanies Cost |
|---|---|---|---|
| Fleas | Accessory | -1 CHA; reduced rest healing | 3 cats |
| Ticks | Body | -1 CON; HP drain over time | 5 cats |
| Tapeworm | Consumable | Eats half your food items; -1 CON | 7 cats |
| Leech | Legs/Feet | -1 SPD; heals the leech when you take damage | 5 cats |
| Brain Worm | Head | -1 INT; causes random movement in combat | 10 cats |
Parasites are most common in low-health rooms. Maintaining room health above 40 significantly reduces parasite risk. Unlike diseases, Rest nodes cannot remove parasites — only Dr. Beanies can. If you lack the cat currency for removal, you may be stuck with a parasite for an entire run. Prioritize room health furniture early in your House setup.
| Feature | Diseases | Disorders | Birth Defects | Parasites |
|---|---|---|---|---|
| Permanent | No | Yes | Yes | No (removable) |
| Max Stack | Unlimited | 2 per cat | Varies by body | 1 per slot |
| Positive Aspect | No | Yes (dual-natured) | No | No |
| Removal Method | Rest, items, abilities | None | None | Dr. Beanies |
| Primary Cause | Low room health | Events, trauma | Inbreeding | Dirty rooms |
| Affects Run? | Yes | Yes | Yes (carried from House) | Yes |
| Curable Mid-Run? | Yes | No | No | No (post-run only) |
| Slot Blocking | No | No | Sometimes | Yes |