So I just disabled animals becoming old boomers, but that makes every animal disappear. I'm looking for a solution because animals spawned by eggs will disappear.

To replicate, set any animals' Elderly config to 0, and they will disappear instantly

Can confirm this: https://streamable.com/o605pc
Happens to naturally spawned livestock as well.

I want a way they can live forever without turning into old boomers and Thanos eventually killing them

The cause is that unfamiliarized animals will be removed after 125% of their lifespan. It‘s a bit silly that they still get removed when they can‘t actually get old.

A cheap workaround is to set the elder days to high numbers. Make sure not to get near max int, something like 2147483000 worked for me. This will let animals be adults for over 20.000.000 default ingame years.

I just wanted to see the unfamiliarized animals get along with animals from other mods and not worry about vanishing

It's a relief to see this is getting a solution

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