Camp spirits only appear in cases where a human body has been burned alive and left alone. It's unclear how they form, but scientists have narrowed it down to something in the bones reacting to long-term exposure to ashes. They were common during the witch trials and often reproduced through a method of indirect induction, wherein they'd intentionally cause mischief that led to suspicions of more witches.

Camp spirits are much rarer nowadays, but not entirely extinct. They've evolved to live much longer and learned a system of governance that allows them to induce new generations through coordinated mischief and subterfuge on nearby human towns.