Patch 1.1 changes how Stimulation, inbreeding, birth defects, Mutation, and inherited voices work; old 1.0 behavior remains available only through a legacy beta branch.

Mewgenics 1.1.21039 changes the inheritance rules enough that older breeding advice can be wrong. The main branch now treats Stimulation, inbreeding, birth defects, and Mutation differently from version 1.0.
Exact breeding changes
- High amounts of negative Stimulation received fixes.
- Stimulation no longer treats a parent's birth defect like a positive mutation.
- Higher Stimulation reduces the chance that parental birth defects are inherited.
- Stimulation has less effect as a kitten becomes more inbred.
- Greater inbreeding significantly raises the chance of inheriting a parent's birth defect.
- Mutation no longer rerolls mutations or birth defects already present.
- Mutation rolls only simple +2/-1 stat mutations through 10; points above 10 raise the chance of effect-bearing mutations.
- A parent's voice now has a 75% inheritance chance instead of 98%.
These are rule changes, not a complete breeding recipe. A useful pairing still depends on the two cats visible in your house and the traits you want to preserve.
Version 1.1 is live on the main branch. The developer keeps legacy versions available through Steam beta branches for players who intentionally want version 1.0 behavior.
Sources
QUICK ANSWERS
Questions players ask next
What changed about Stimulation in Mewgenics 1.1?
High negative Stimulation issues were fixed, positive Stimulation now reduces inheritance of parental birth defects, and its effect is reduced for more inbred kittens.
What happens above 10 Mutation?
Up to 10 Mutation, the stat rolls simple +2/-1 mutations; additional Mutation increases the chance of effect-bearing mutations.
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