Between-run upgrades that persist across all runs. NPC unlock trees, optimal upgrade order, and the pipe system that ties everything together.
The pipe system is the backbone of meta-progression. Pipes connect your house to various NPC locations, unlocking access to their services. Each NPC requires a specific pipe connection, and some pipes require previous upgrades before they become available.
Completing all meta-progression requires approximately 45 cats total across all NPC upgrade tracks. This includes cats rescued during runs, donated to Tink, sacrificed for Dr. Beanies, and used for Frank's room expansion. Plan your breeding program accordingly.
Each NPC offers a progression path with tiers or milestones. Investing in the right NPCs at the right time dramatically accelerates your runs.
Butch runs the in-run shop. Upgrading his inventory unlocks better items, more stock, and discounts. Each tier requires zone progression and gold:
| Tier | Zone Requirement | Gold Cost | Unlocks |
|---|---|---|---|
| 1 | None | Free | Basic potions, common items |
| 2 | Sewers cleared | 500 | Uncommon items, mana potions |
| 3 | Junkyard cleared | 1,200 | Rare items, ability reroll scrolls |
| 4 | Industrial Wastes cleared | 2,500 | Epic items, stat boosting gear |
| 5 | Archivist defeated | 5,000 | Legendary items, set pieces |
| 6 | Four Wardens defeated | 10,000 | Mythic items, unique class gear |
| 7 | Genetic Core cleared | 20,000 | All items available, permanent discount |
Frank adds rooms to your house, enabling specialization. Cost is based on cats rescued (not donated — rescued during runs):
| Milestone | Cats Rescued | Rooms | Note |
|---|---|---|---|
| Start | 0 | 2 | Kitchen + 1 room |
| 1 | 1 | 3 | Unlocked immediately after first rescue |
| 2 | 25 | 4 | First major milestone |
| 3 | 60 | 5 | Late-game expansion |
| 4 | 100 | 6 | Maximum rooms |
Tink upgrades your genetics information panel through 6 milestones. Cost is cumulative kittens donated. Every non-essential kitten should go to Tink early — the information unlocks are worth more than any single cat.
| Kittens Donated | Unlocks | Why It Matters |
|---|---|---|
| 1 | Fancy Bow (cosmetic) | Decorative only. |
| 11 | Base Stat Visibility | See the 0–7 base stat scale. Critical for evaluating breeding candidates vs. gear-inflated stats. |
| 21 | Inbreeding Status | Shows genetic degradation level (None → Slight → Moderate → Severe). Prevents accidental Moderate crossings. |
| 31 | Sexuality, Libido & Orientation | Shows Sex, Orientation (Straight/Gay/Bi), Libido (Low/Average/High). Filter for Straight/Bi + Average/High Libido breeders. |
| 41 | Marking System | Unlocks visual marker icons for bloodline tracking (Stars = studs, Shapes = generations, Houses = strays, Swords = combat). |
| 51 | Aggression Levels | Shows Low/Medium/High aggression. High-aggression cats in the Breeding Room disrupt breeding cycles. |
| 61 | Social Icons | Love/Hate icons predict breeding compatibility and pairing frequency. |
The 11-kitten base stat display and 21-kitten inbreeding status are the two most impactful unlocks. Rush these before Butch Tier 3. The 31-kitten sexuality/libido unlock enables population culling (remove Gay/Low-Libido cats, freeing room slots for productive breeders). See the Genetics page for the full Tink milestone table and Rule of 4 population management.
Baby Jack provides permanent run-wide bonuses. These are simple one-time upgrades:
| Upgrade | Cost | Effect |
|---|---|---|
| Extra Life | 1,000 gold | Start each run with +1 extra life for the party |
| Gold Finder | 1,500 gold | +20% gold from all sources during runs |
| Exp Boost | 2,000 gold | +15% experience gain for all cats |
Tracy sells furniture for your house between runs. Her inventory expands as you progress:
| Tier | Requirement | New Stock |
|---|---|---|
| 1 | None | Basic beds, food bowls, litter boxes |
| 2 | 5 cats rescued | Cat trees, scratching posts, window perches |
| 3 | 25 cats rescued | Exercise wheels, premium beds, water fountains |
| 4 | 50 cats rescued | Robo set pieces, luxury couch |
| 5 | 75 cats rescued | Aquarium, dead rat, toxic waste, bleach jug |
Dr. Beanies offers permanent stat-boosting inventions. Each cat can receive up to 5 injections — one per stat. Each injection gives +1 to the chosen stat permanently.
| Invention | Stat | Materials Required |
|---|---|---|
| Muscle Serum | STR | 3 Mutagen + 2 Iron Ore |
| Brain Tonic | INT | 3 Mutagen + 2 Crystal Shard |
| Reflex Enhancer | DEX | 3 Mutagen + 2 Feather |
| Toughness Formula | CON | 3 Mutagen + 2 Scale |
| Charm Elixir | CHA | 3 Mutagen + 2 Gem |
Each invention requires a short quest to unlock before it can be crafted. Quest steps vary but generally involve finding a specific item during a run or defeating a particular enemy type. Mutagen is the bottleneck material — prioritize collecting it whenever you see it in shops or events. Each cat can receive all 5 injections (one per stat), so a fully Beanies-boosted cat has +5 total stats.
Resources are有限的 early on. Here is the recommended sequence to maximize your progression efficiency:
Prioritize Butch's shop upgrades to Tier 3. Uncommon items and ability reroll scrolls dramatically improve run consistency. This is your first gold sink.
Phase 1Expand to 4 rooms. This unlocks room specialization — breeding room, isolation ward, nursery, and general use. Essential for genetic progress.
Phase 1Rush Tink to 11 kittens (base stat visibility) and then 21 kittens (inbreeding status). These two unlocks transform breeding from guesswork to data-driven decisions.
Phase 2Baby Jack's Extra Life provides run safety. Tracy's furniture expands room stats. Tink's 31-kitten unlock reveals sexuality/libido, enabling Gay/Low-Libido culling to free room slots.
Phase 2Start Dr. Beanies invention quests once you have steady Mutagen income. Push Butch to Tier 5-7 for legendary and mythic items. These are end-game investments.
Phase 3Butch early = better items in runs = more successful runs = more cats rescued and more gold. Frank's room expansion enables the breeding quality needed to generate strong cats. Tink prevents inbreeding disasters that waste generations of breeding. Dr. Beanies and high-tier Butch are force multipliers that only pay off once your base is solid.