So far there is no official evidence that the Universal Slug exists, and that it's only a rumor.
Trivia
- Redhook says this slug is non-existent, but then again that's what he also said about Fusion Shots, Vitalis Crystals, Oderless Pluming and the Energy Elemental Slug.
Fans' Theories
- The Universal Slug was made by all 5 Elemental Slugs as the main slug of all Slugs and it is a Guardian Slug. Originally, it was so powerful that it can travel into a different universe and still protect the Guardian Portal, but this is still just theories.
Appearances
- The Hard Part (Mentioned only)
- Slugterra: Return of the Elementals (Mentioned only)