- "These massive cubes of gelatinous goo can dissolve almost anything quickly. They feed on intense human emotion. Salt is a powerful weapon against them."
- ―The Troop official site's description of the Gelatinous Cube
Gelatinous Cubes are monsters which resemble massive cubes made of gelatinous goo.
Apparently, Gelatinous Cubes have rarely appeared since the early 16th century.
A Gelatinous Cube infiltrates Lakewood High through the ventilation system and dissolves the janitor.
The Gelatinous Cube is captured, but injured from the salt's effect on it, and is eventually restored by Felix's emotional memories. It then restores Jake and Hayley to their original bodies and was befriended by Felix.
When the captive Gelatinous Cube's cell is unlocked by Fraido, Gus and his servants attempt to dispose of Mr. Stockley by throwing him into the Cube, but the Cube, unwilling to harm Mr. Stockley, does not dissolve him.
The Cube is later seen back in its cell, and is released by Fraido and Gus along with the other captive monsters, but is presumably recaptured.
Gelatinous Cubes are apparently intelligent monsters, and can understand English.
Gelatinous Cubes appear as large, moving cubes made of green gelatin.
The Gelatinous Cube is able to dissolve anything swallowed whole in a matter of seconds and any two creatures swallowed but removed before the Cube can dissolve them, to swap bodies. Apparently, Gelatinous Cubes can also understand English and bear a human or near-human level of intelligence. They also appear to be able to control whether or not to dissolve swallowed victims, as in "The Next Stop: Lakewood", the Cube swallowed, but refused to digest, Mr. Stockley.
Gelatinous Cubes also feed on intense emotions, which strengthen them and allow them to regenerate.
Salt is extremely harmful to Gelatinous Cubes.
- The Gelatinous Cube is similar in some aspects to the Mood Slime from Ghostbusters II.
- In "The Next Stop: Lakewood", the Gelatinous Cube leaves its unlocked cell shortly after seemingly digesting Mr. Stockley. However, when the captive monsters are released, the Cube is back in its cell.
- The Gelatinous Cube is based off a Dungeons & Dragons creature of the same name.
- Also resembles Jiggles,the Kowalski´s monster from the seires The penguins of Madagascar