Ūnoculolīmāx viridis is a small slug easily identified by having only two tentacles (instead of four), one optical and one olfactory, and by its vivid colouring: green with dark green markings and brown underbelly with yellow spots crossed by a bright yellow strip. Ūnoculolīmāx viridis feed on fungi of all kinds, and their mucus sometimes produces unsavoury smells, depending on what they ate.

Ūnoculolīmāx viridis can be found in the wild, but have also been cultivated by magic-folk, particularly of the Vrac̆ line. In the 17th century, Irma and Zoe Vrac̆ found that Ūnoculolīmāx viridis can safely digest the Fragrans lētum mushroom, and developed a complex process where a patient was kept asleep while their stomach was opened and Ūnoculolīmāx viridis were introduced to clear the mushroom infection. The process was incredibly dangerous, but was, and still is, the best method to against Fragrans lētum infection. Nowadays, with modern surgery equipment and methods, the procedure offers 76% success rate if the infection is caught on time.