The Invisible Isopod is a large humanoid isopod who is invisible, as his name states, and is transparent with a light-blue hue. He has a large "I" on his chest and a set of six-pack abs below that. His antennae are positioned in a way that resembles a handlebar mustache.
Powers and abilities
As stated before, the Invisible Isopod is invisible, a power which he can use in order to sneak up on his foes. He is also strong, as he can lift up Barnacle Boy by his underpants.
The first issue of the Aquatic Adventurers comic implies that, under certain lights, people are able to slightly see him.
Role in comic book
In the comic Lo, There Shall Be A Catered Affair!, after the Flying Fish goes into Mr. Krabs' office to sign his comic book, SpongeBob and the rest of the Aquatic Adventurers notice he is missing. SpongeBob compares this to the story in the Aquatic Adventurers' comic book, where the Invisible Isopod snuck into the team's headquarters in hopes of abducting them one by one.
One by one, the members of the Aquatic Adventurers go into Mr. Krabs' office to sign his comic book, causing SpongeBob and the team to believe that the Invisible Isopod is actually in the Krusty Krab. After being scared by a mailman, SpongeBob says that they are too vulnerable to the Isopod's attacks and that the team should hide in an enclosed space. Soon, SpongeBob and the Aquatic Adventurers are hiding in the bathroom.
While looking for everyone, Mr. Krabs opens the bathroom door, causing the Aquatic Adventurers to think he is the Invisible Isopod and attack him. They soon realize their mistake and complain about the Invisible Isopod never being in the restaurant, due to the event thrilling them. Barnacle Boy then states that he knew the Invisible Isopod was never there in the first place, until he is suddenly given a wedgie by the Invisible Isopod, who calls Barnacle Boy a weenie.
The Invisible Isopod then appears in a bonus gallery poster later in the same comic book, alongside nearly every other Mermaid Man villain to exist.