Threshers are blue Metal element Slugs. It is the favourite Slug of Sergent Slug, the owner of Club Slug. When they transform after hitting 100 MPH, they gain characteristics of both a tiger and a shark. The thresher slug is named after the Thresher shark famous for its bony tail.
- A famous Thresher is Buzzsaw, who belongs to Eli Shane.
- Another famous Thresher is Butch, who belongs to Sergent Slug.
- A ghouled Thresher is called a Thrasher.
A Megamorph Thresher is first seen in an official art in Slugterra: Return of the Elementals, while its official appearance is first seen in the Slugisode Trick or Cheat! and Slugterra: Into the Shadows.
- Protoform Abilities - Can chomp through things.
- Sawtusk - Huge chomping bite.
- Throttlebite - Curls into a flat circle and spins like a saw blade, boney spines on the outside to slice things.
- Trillioblade - Flings saw blades from its tail.
- Blasterslash - Chomps on to an opponent's blaster then spins like a sawblade, sawing it in half.
- Magma Saw: "Thresher"+"Forgesmelter" - Forms a superheated spinning magma sawblade that spews lava from its sides and can easily melt and cut through most metals.
- Slicing Rope: "Thresher"+"Polero" - The Polero grabs the Thresher, spinning it at high speeds, leading to a bolo-like appearance.
- Toxic Tusk: "Neotox"+"Thresher" - TBD. It hasn't officially appeared in show yet.
Being a useful slug in close quarters combat in addition to a a common one, Threshers are good slugs to have at all times, due to their versatile array of abilities. It's first two moves are useful in attacking slugs that make contact with it, allowing it to continue its path towards the opponent, whereas it's Trillioblade move enables it to attack opponent's out of range. Blasterslash is somewhat a luck-based move, as it involves the Thresher making a direct hit to the opponent's blaster to successfully use, but its worth it as it can completely disable your opponent.
The only downside to the Thresher is that 3 out of 4 of its moves need to make contact with the target to become useful, as an opponent would have an easy time to dodge a Thresher while it is moving in the air. Similarly, slugs with long ranged moves can incapacitate a Thresher before it even uses an attack. This weakness, however, can be exploited by firing another slug in tandem, as your opponent would either have to dodge the Thresher or waste a Slug on it, allowing a second slug to have an easier chance of hitting the opponent.
Outside of battle, a Thresher is useful in situations where its slinger is trapped, as it is strong enough to shred rocks and jungle flora that may restrain its slinger, even when in protoform.
- The World Beneath Our Feet Part 1 (First appearance)
- The World Beneath Our Feet Part 2
- The Trade
- Club Slug
- The Slug Run
- Endangered Species
- The New Kid Part 1
- The New Kid Part 2
- The Journey Home
- The Gentleman and the Thief
- The Hard Part
- The Return
- Mission: Improbable
- Keys to the Kingdom
- The Thrill of the Game
- Back to Blakk (Appears in flashback(s))
- Bandoleer of Brothers
- Light as Day
- Slugterra: Ghoul from Beyond
- Slugterra: Return of the Elementals
- The Fall of the Eastern Champion (Appears in flashback(s))
- The Lady and the Sword
- Slugterra: Into the Shadows
- A Thresher is the first slug to ever be shot in the series.
- A Thresher, alongside a Dirt Urchin, are one of the few things that could pop a Bubbaleone.
- In a Slugisode, it is shown that when a Thresher isn't fired enough, it can have a chipped tooth.
- While they live in seasides and have the transformed appearance of a shark, a Thresher is Metal-Type instead of a Water-type.