I think a better way to control follower numbers without resorting to limiting thrall and pets would be to implement a rat-carrying plague mechanic. How I would implement this is to make it so that for every 10 thralls of pets there is a 10% chance for rats to spawn. When rats spawn they would target the players thrall pots and animal feeders. When they come in contact with them there is a 25% chance of infecting food with the plague which will cause thralls who consume it to contract the plague. Rats would also bite thralls and pets potentially giving them the plague. if players have cats, lions, tigers, panthers, or snakes these pets will consume them which can help control rats. Once rats have spawned they can escape the base and spread to nearby bases spreading the plague to them as well. One could make it so that a grate will appear in a person’s base if they have more than 50 thralls which indicates a rat infestation that needs to be cleared out or will spawn rats at a faster rate. If thralls contract the plague they will need to be given health potions and they will eat more as they will lose health. Adding such a mechanic would naturally control the number of followers while at the same time making use of currently useless animals. We have stray cats and rats as pets which do not do anything so this would give them an actual reason to have as pets. If a player wanted to they could capture rat pups which when they become adults would seek out traps and spring them during raids just like they are used in the modern world to clear out mine fields.
That sounds like an entire video game on its own.
Log in to a plague ridden keep 
You see the future of this mechanic, don’t you. After plague, vaccination will have to be included…
Conan exiles already have rants about, slavery, violence, nudity…
Next thing will be that it promotes vaccination too 
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Ps. I love the effort of this idea however, keep it coming fellow exile @Putin4ever
It adds a biological warfare element that fits into the Conan world. I bet the Acheronians were not above creating plagues to attack their enemies. I am always curious why survival games do not put plagues into their games.
i dont think vaccinations would fit into the conan universe. It would also defeat the purpose of creating this type of mechanic. The purpose would be to create a natural way to limit followers. if a person wanted to have thousands of thralls they would have to deal with constant plagues.
Let’s take it from the beginning then.
A way to naturally limit your followers already exists. It’s called thrall pot.
But it doesn’t work years now. There’s nothing more natural to die from starvation 
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Then again you seek for a perfect mechanism to work when the standard existed don’t. Didn’t you listen? Your thralls cannot protect your base from raids years now.
I do understand where you are getting it, but i don’t see it coming, yet like i said above i like your creativity. Don’t stand down, keep it coming.
Ps. Maybe there’s not a natural way to limit your followers, but a cap exists already 
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It is what I would do if I created a game like Conan exiles. I would also have storms which would damage buildings over time, invasions from outside which target foundations etc. Maybe termites which would attack base foundations and you would need spiders, reapers, or scorpions to control them.
Play Siptah and allow Maelstrom to dmg your buildings on your settings 
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You should create that game, I bet dollars to doughnuts that you would very quickly find out how many people hate games like this.
I could be wrong, of course, you might get rich and then you could make fun of me for trying to bring you down. If that were to happen I’d be happy to applaud you, but I don’t think it would. People who enjoy this kind of brutal game play already play PvP.
That sounds like an interesting new idea for a purge, but a bad idea for a game mechanic to controll thralls.
Most people like the fact that their thrall numbers are under their own control, they can choose with thralls to delete if they want new ones. Very few people would like having the game “control” their thralls by killing the ones they like and care about.
But seriously though, think more on how you could turn that into a purge idea. That would be cool for everyone, rather than just a few people, having more variety in purges could be beneficial to everyone.
I appreciate the creativity and planning behind your idea. Unfortunately, I believe adding another mechanic into already poorly maintained code would be problematic.
Weaponized, sorcerous plagues were explicitly used in the novel Hour of the Dragon. The villain of which was, in fact, a resurrected Overlord of Acheron.
Whack-a-Mole?