some sort of semi perm castle defense mobs. A couple of ways they could be done. Some sort of tinker/chanter combination or something at the castle shop.

Off the top of my head I would add it as a castle feature that would give it a spot or stand in a room. This could be added and removed like a door. Then somebody, a tinker or chanter would work on it to give it a usable form, possibly customizable like choosing from a range of body types. Some might take longer or more ingots if an ingot cost was involved. This persons skill would help determine the skills of the guardian. Perhaps some skills or spells to improve certain aspects as well

Then they could be given items which they would wear and wield. I'd probably ok equip make said items non returnable so they are lost forever. The guardians themselves perhaps would return if defeated after reboot and the castle feature would add a certain cost per month of upkeep. Similar to a room. The guardians wouldn't be lootable.

Just a rough idea. Adds another level of castle customization.
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If you say plz because it is shorter than please, then I will say no because it is shorter then yes.