Scientists have discovered a zombie slug controlled by fungi.

According to a study published in the journal PLOS Bacteria, researchers have found that the parasite fungus also controls their thoughts and forces them to infect other insects. The researchers call them “zombie slugs” infected by a fungus called Massospora, a psychedelic fungus that contains chemicals commonly found in psychedelic mushrooms.

After infection, fungal spores can erode the genitals, buttocks, and abdomen of the slugs and replace them with fungal spores that can spread to other slugs.

Because it has a 13- or 17-year life cycle, living underground and not appearing until more than 10 years later, it is difficult to study how fungi infect the slug.