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Mewgenics Stat Inheritance: Why 5.85% of Kittens Are Perfect

By BrokenBuilds Wiki7 min readUpdated

Mewgenics Stat Inheritance: Why 5.85% of Kittens Are Perfect

Roughly 1 in 17 bred kittens, about 5.85%, inherit the higher of each parent's seven stats. That number is not a guess. It falls out of a single decompiled formula, and once you understand the math you can plan breeding rooms around it instead of praying for good rolls.

This guide walks the formula end to end, then runs three worked examples covering different parent matchups.

The Seven-Stat System

Every cat has seven core stats:

  • STR scales melee damage at +1 per point
  • DEX scales ranged damage at +1 per two points
  • CON sets max HP at CON x 4
  • INT sets mana regen per turn equal to the stat value
  • SPD controls grid movement and turn order
  • CHA sets max mana at CHA x 3 and feeds the breeding compatibility check
  • LCK sets crit chance at 10% baseline plus 2% per point above or below 5

Bred kittens roll their base values in the 3 to 7 range. Class modifiers stack on top after birth, so a item:fighter rolled at STR 7 stays ahead of a Fighter rolled at STR 4 forever. Base rolls are permanent. You get one shot per kitten. For a roundup of which collars amplify which stat rolls, see the Mewgenics Best Starter Classes guide.

How Each Stat Rolls

When two parents breed, the game runs seven independent rolls, one per stat. For each roll it tags the higher-statted parent as "better" and the lower as "worse," then checks the room's Stimulation value and applies this formula:

P(better) = (1 + 0.01 * Stimulation) / (2 + 0.01 * Stimulation)

At Stimulation 0, that resolves to 1/2, a coin flip. At Stimulation 100, it resolves to 2/3, or 66.67%. The function is asymptotic. P(better) approaches but never reaches 100%, no matter how high Stimulation goes.

Each of the seven rolls is independent. STR has no influence on DEX, and DEX has no influence on CON. The same Stimulation value feeds all seven rolls, but the rolls themselves are separate events. That independence produces the 5.85% figure.

The Perfect-Roll Math

A "perfect" kitten inherits the higher of each parent's stats across all seven rolls. Because each roll is independent, you multiply the probabilities:

P(perfect) = P(better)^7

At Stimulation 100, P(better) is 2/3. So:

P(perfect) = (2/3)^7 = 128 / 2187 = 0.0585 = 5.85%

That is the number. About 1 in 17 kittens hits the upper-bound roll on every stat at Stimulation 100. The community-cited "around 6% perfect" figure on mewgenicswiki.org matches this exactly.

Lower Stimulation collapses the number fast. At Stim 50, P(better) is 60%, so P(perfect) is 0.60^7, about 2.8%. At Stim 0, you are betting on seven coin flips landing heads, which is 0.5^7, about 0.78%.

Stimulation 95 is the practical sweet spot. It guarantees passive ability inheritance and pushes P(better) to 65.5%, so the perfect-roll rate sits at 5.2%, just shy of the Stim 100 ceiling.

Worked Example 1: Similar Parents

Setup:

  • Father: STR 6, DEX 6, CON 5, INT 5, SPD 6, CHA 5, LCK 6
  • Mother: STR 5, DEX 5, CON 6, INT 6, SPD 5, CHA 6, LCK 5
  • Stimulation: 100

The father wins STR, DEX, SPD, and LCK. The mother wins CON, INT, and CHA. Each stat has a 2/3 chance of going to the winner.

The expected stat total per kitten is 0.667 * higher + 0.333 * lower summed across all seven stats. Run that out and you get roughly 39.7, above both parents' totals of 39 and 38 because each axis skews toward the better value.

The probability of the kitten inheriting all four of the father's higher stats AND all three of the mother's higher stats is (2/3)^7 = 5.85%. A near-perfect kitten with six out of seven hits the upper roll lands at about 20.5%.

Evenly matched parents do not produce massive single-roll upside. They produce a steady stream of kittens close to the maximum total, which stabilizes a line without dragging it back.

Worked Example 2: Asymmetric Parents

Setup:

  • Father: STR 7, DEX 7, CON 7, INT 7, SPD 7, CHA 7, LCK 7 (a max-stat parent)
  • Mother: STR 3, DEX 3, CON 3, INT 3, SPD 3, CHA 3, LCK 3 (a min-stat parent)
  • Stimulation: 100

The father is the better parent on every stat. Each roll has a 2/3 chance of inheriting his 7, and a 1/3 chance of inheriting her 3.

The expected value per stat: 0.667 * 7 + 0.333 * 3 = 5.67. Across all seven stats, expected total is about 39.7.

Probability of a perfect kitten (all sevens): 5.85%. Probability of an all-threes kitten (every roll picks the worse parent): (1/3)^7 = 0.046%, or about 1 in 2187.

The asymmetric pairing has the same perfect-roll rate as the symmetric one. What changes is the floor: a "bad" roll here gives you a 3 instead of a 5. You get lots of mediocre kittens with mixed totals.

This is why experienced breeders pair two strong parents instead of dragging a weak parent up through repeated breedings. The math does not reward dragging weak genes forward.

Worked Example 3: The Perfect Roll

Setup:

  • Both parents have all sevens (or you have already bred up to a near-max pair)
  • Stimulation: 100
  • Comfort: 50 (boosts breeding attempt frequency)
  • Twin probability per litter: 17.36% (average fertility)

You run breedings until a perfect kitten lands. Each kitten has a 5.85% chance of being perfect. The expected number of kittens to produce one perfect roll is 1 / 0.0585, about 17.

Twins boost throughput. About 1 in 6 litters delivers two kittens, so the expected litters per perfect kitten drops to roughly 14.5.

If your breeding pair breeds once per night for 30 nights, you produce around 35 kittens. The probability of zero perfect rolls in that span is (1 - 0.0585)^35, about 12%. So the probability of at least one perfect kitten is 88%.

That is what a month of disciplined breeding buys you. A room running for 30 nights at high Stimulation reliably produces at least one perfect kitten, often two or three.

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Practical Implications

Three rules follow from the math:

Run many breedings. A single breeding has a 5.85% chance of perfection at best. The reliable strategy is volume. Set up a high-Comfort, high-Stimulation room and let the pair breed for as many nights as you can spare.

Retire parents at diminishing returns. Once both parents have all sevens, additional breedings offer no upside. Move the perfect kitten into a new pairing with another strong cat. Your line improves by combining strong parents from different bloodlines.

Stack Comfort, Stimulation, and Fertility. Comfort scales breeding attempts per night by sqrt(1 + 0.1 * Comfort), a 2.45x multiplier at Comfort 50. Stimulation shifts per-roll odds toward the better parent. Fertility (a hidden coefficient between 1.0 and 1.25) sets the twin rate. All three stack.

The math is fixed. Your job is to maximize attempts and let the 5.85% land on its own. For room layouts, lover bonuses, and the full compatibility formula, the Mewgenics Breeding Guide covers the upstream mechanics that feed this math.

What's Next

For the full breeding compatibility formula, lover coefficients, and birth defect math, see the Mewgenics Breeding Guide linked above. The Mewgenics Breeding Calculator ships next sprint with per-stat probability bars, expected litter outcomes, and Stimulation-versus-Comfort tradeoff curves keyed to your actual cats.

Once you have a perfect kitten, the next decision is which collar to put on it. The Mewgenics Class Tier List ranks every collar against the current meta so you can match the stat spread to a role.

Bring the parents. The math will handle the rest.