There's one healer slug who stands out from all the others, and that's Eli's slug DOC, the legendary Energy Elemental slug. Doc was once part of Billy's arsenal until, Billy not knowing Doc's true value, rejected him and was rescued by Eli. He's Eli's faithful companion, an ultimate healing weapon and eager to prove himself. Extremely powerful and more ancient than your average slug, Doc's got slug moves most people have never even seen before!
- Protoform Abilities - Minor healing powers, like a warm compress, topical ointment or localized antidote.
- Medici - Shoots a healing ball of light that is absorbed by the slug or person it is shot at. Cures internal ailments.
- Healswarm - Emits a powerful light glow that can heal a ghouled slug.
- Skinsplint - Spins a protective cocoon of light around an injured or broken area to heal it.
- Lightshield - Small sparks form a protective wall or bubble like a force field to protect against toxins.
- Slugmage - Casts protective shell of light over a slinger's slug arsenal to prevent ghouling.
- Healadin - Swarm of sparks forms a suit of protective light armor. The slinger becomes impervious to ghouls.
- Medest (unofficial name): "Doc" + "Charger" - Forms a massive healing ball of light that reverses the effects of a Vamparo.
- Billy rejects Doc, so Eli takes him in. (The Slugout)
- Doc cures a Ghoul Slug, thus revealing he's a Healer and can cure ghouls, thus saving the day. (The Slugout)
- Doc neutralizes Dark Water with the help of some Fandango slugs and saves Bullseye Cavern. (Shadows and Light)
- Doc cures ghouled Mecha-Beasts. (Mecha Mutiny)
- Doc cures a Cryptogrif, a ghouled Hypnogrif, freeing the people in Caverna Mall Cavern from Mr. Saturday's control.
- Doc liberates all the ghouls in one of Blakk's Ghoul Depots. (The New Kid Part 1)
- Doc heals weakened Guardian Slugs and is rewarded with Guardian status however it results in him leaving the Shane Gang. (What Lies Beneath)
- Doc returns to the Shane Gang and helps heals the ghouled slugs in Blakk's stronghold, thus putting an end to Blakk and his master plan. (Light as Day)
- Doc cures Burpy and several slugs, but gets sucked up into the Slug Tunnels during battle, but he's saved by Burpy and then helps save Eli and the day. (Ghoul From Beyond)
- Doc is revealed to be the one and only Energy Elemental Slug and becomes a target of the evil alliance bent on destroying SlugTerra, but Doc manages to cure Will Shane and the rest of The Elementals, and temporarily weakens The Goon and later helps to undo the damage caused to the The 99 Caverns. (Return of the Elementals)
- Doc does a fusion for the first time (with Charger) to cure Master Lian. (The Return of the Eastern Champion)
List of Elemental Relatives
- Doc was the first and only Elemental Slug introduced before the events of Slugterra: Return of the Elementals, and was also the only one to not have been ghouled. And was the first Elemental to achieve Guardian status.
- Doc doesn't need to be controlled by Slug Fu because he and Eli are already good friends and he is used to having a slinger to sling him, however the other Elementals are used to being solo for at least 300 years or so.