Sinister Slug is a recurring villain from Spongebob Squarepants. He is one of the many foes of Mermaid Man and Barnacle Boy. He is a terrorous slime creature that lives in the sewers.


In "The Bad Guy Club for Villains", Sinister Slug crawled out of the sewer and wormed up to a gathering of other villains. These were Man Ray, The Dirty Bubble, Atomic Flounder, and Jumbo Shrimp. They were banding together to make a team, known only as BGATFBC. Mermaid Man and Barnacle Boy watched them from an alley and suspected something was up so they tried to stop them.

The BGATFBC held their meeting at Hotel Evil, where Mermaid Man and Barnacle Boy showed up on the scene with a few other superheroes and fought with them. In battle, Sinister Slug slid up the wall and vomited a ball of slime at Mermaid Man. Mermaid Man jumped out of the way and the slimeball blasted Atomic Flounder instead. The slimeball was so sticky that it immobilized Atomic Flounder and stuck him to the ground.

Mermaid Man used The Bronze Hairnet's hairnet to capture all of the BGATFBC members and make them talk. They said that "BGATFBC" stood for "Bad Guys All Together For Book Club" and that they couldn't imprison them for reading. Mermaid Man said that this was right and let them continue their book club.

Powers & Abilities

  • Slimeballs - Sinister Slug can vomit slimeballs at people. When struck by the slimeballs, the target becomes immobilized and incapacitated, as the sticky slime leads to them becoming stuck to the floor.
  • Climbing - Sinister Slug is sticky enough to climb up the walls.




           SpongeBob.png Villains

Main Villains
Mr. Krabs | Plankton | Karen Plankton | Mrs. Puff

Major Villains
Flying Dutchman | Man Ray | Sinister Slug | Jumbo Shrimp | Atomic Flounder | Dirty Bubble | Bubble Bass | Plankton Family | DoodleBob

Movie Villains
The SpongeBob Squarepants Movie:
Mr. Krabs | Mrs. Puff | Plankton | Dennis | Karen Plankton | Victor | Cyclops | Boat Jacker | The Thug Tug Gang
The SpongeBob Movie: Sponge Out of Water:
Plankton | Mr. Krabs | Burger-Beard
The SpongeBob Movie: Sponge On the Run:
Plankton | Mr. Krabs | Karen Plankton | King Poseidon

Other Villains
Every Villain Is Lemons | Abrasive SpongeBob | Alaskan Bull Worm | Puffy Fluffy | Sergeant Sam Roderick | Tattletale Strangler | Lord Poltergeist | Carl | Big One | BlackJack SquarePants | Evil Alien Jellion Overlord | Sea Bear | The Moth | Hash-Slinging Slasher | Con Man | Master Udon | Evil Syndicate | King Gorge | The Mawgu | Don Grouper | Animatronic Hieronymus Glove | Gordon | Coupe | Triton | The Fisherman | Madame Hagfish | Dead-Eye Plankton | Art Appraiser | Miss Gretel Puss | Planktonamor | Dreaded Patrick | Karen 2.0 | Captain Scarfish | Dragon Jellyfish | The Jellions | SpongeBot SteelPants | Robot Plankton | Robots | Globulous Maximus | Flats the Flounder | ToyBob | Cuddle E. Hugs | Gale Doppler | Mini Doodles | Plankrab | Doctor Negative | Jelliens | Seymour Scales | Catfishstress | Octopus King | Swamp Natives | Hoodoo Guru | Earworm | Krabby Patty Zombies | Plankton's cellmates | Alternate Reality Mr. Krabs

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