Cloak of symbiotic protection

A cloak of symbiotic protection was a very rare type of enchanted cloak infused with a living, though immobile and seemingly unintelligent, symbiotic substance.

Powers
Whoever wore one of these cloaks was impervious to the harmful effects of green slimes, olive slimes, obliviaxes, violet fungi, yellow musk creepers, yellow mold, and russet mold. In addition, the wearer's immune system became stronger in terms of fighting off the hazardous spores of many types of fungi, including ascomoids, basidironds, and myconids.

As a negative consequence of wearing this cloak, the symbiotic life form would drain a small amount of vitality from its user every time it was put on. Alternatively, it would drain a small amount once every two days if worn continuously. The cloak also made its wearer colorblind, though only for the duration of it being worn.

Besides vitality, the symbiotic life form fed upon and neutralized spores and nearly all other forms of microscopic, airborne life. Because of this, wearers had a lower chance of contracting some diseases.

History
What living substance infused these cloaks was and its origins were both completely unknown to scholars. Naturalists and alchemists alike had attempted to separate them for study, but every time the substance proved impossible to isolate.