Candy People Mutant was a giant blue mutant created by GOLB, who used its evil breath to fuse the Cake People together into one giant being. It mutated one of the Gumball Guardians into the Gumball Guardian Mutant. It attempted to rampage the Candy Kingdom. On its way there it completely destroyed the Tree Fort, shattering BMO’s glass and frightening Jake. It appeared to have a weakness to music, because once BMO started singing it stopped in its tracks and screeched in pain. Once GOLB fused with Betty Grof, it disappeared into nothingness.
The Candy People Mutant appears to be a giant, blue, mutated four legged creature. The heads of the Cake People that fused with it writhe in agony all over its body. It has giant pillars distending from its back that emit smoke. Its tongue is split into many long, thin parts and is shaped like somewhat of a heart. It also seems to have giant eyes all throughout the front of its body.
During the fight, Marceline attempted to save Princess Bubblegum by becoming a giant vampire cloud and smashing the monster. It appeared to have been crushed to pieces, with one of the cake people fused with it remarking "Thanks.". It was shown a few moments later that it had the ability to reanimate itself and completely be restored back to its original being.
One of the Gumball Guardians and The Cake attempted to stop the beast by pinning it down. This turned out to be a poor decision, because not too long after the monster used its tongues to spit a liquid that solidified on contact and mutated the Gumball Guardian into the Gumball Guardian Mutant.
As an attempt to stop the monster, Flame Princess used her elemental fire powers to try and burn the beast alive. She shot fire at its side, however no mark was left, and the beast showed to be only annoyed with her.
- Unlike the Gumball Guardian Mutant, the Cake People Mutant doesn’t seem to be able to assimilate other beings, only eat and mutate them.
- Despite its many faces, only the main head in the front seems to be in control.
- Its other heads that appeared all over it's body seemed to help in the singing in attempt to stop GOLB.
- The status of all the Cake People that were combined into the creature is unknown, as it completely appeared to disappear during the blast that fused Betty and GOLB.