Underfist: Halloween Bash

Irwin, Billy, Mandy, and Grim go trick-or-treating on Halloween night. Billy disguises as a witch, Mandy and Grim portray the Spanish Inquisition, and Irwin acts as Dracula, king of vampires. They have little success collecting candy and decide to head home.

Irwin notices that his life feels like it's passing him by. Meanwhile, Billy, Mandy, and Grim leave him, feeling disappointed after their failed attempt at getting candy from Dracula, who rudely gives them pennies.

Mindy, secretly turned into a witch by an evil marshmallow bunny named Mr. Bun Bun, fools Irwin into opening an underworld portal. The portal releases an army of evil candy warriors terrorizing the neighborhood.

Irwin contacts Hoss Delgado for help. Hoss arrives with soda-candy guns but gets attacked and subdued by the candy warriors. Skarr joins the fight with a robot after his purple pansies are destroyed.

A fierce war erupts between the heroes and candy monsters, with no mercy or rules. Mindy tricks Irwin again, pretending she's being kidnapped by Mr. Bun Bun, leading to her escape into the Underworld.

Hoss and Irwin find a rain-soaked portal to the Underworld, but it turns off when Mindy destroys the diamond powering it. The candy warriors attempt to sacrifice Hoss but keep Irwin alive because of his mummy-like powers.

Mindy creates a potion that turns the warriors into monsters. She plans to use Irwin's powers to make the ultimate candy monster. Hoss, Jeff, Fred, and Skarr devise a plan to reach the Underworld and rescue Irwin.

The candy monsters go on a city rampage. Irwin and Hoss argue during the battle, inadvertently enabling the monsters to absorb Irwin's power and transform into a giant candy monster. Hoss admits his fear of monsters and apologizes.

Mr. Bun Bun reveals he was behind Mindy's transformation and used her to open portals to the Underworld. When he's about to kill Mindy and Underfist, Skarr betrays Bun Bun, kicking him into hot cocoa, which melts him.

Grim, Billy, and Mandy, now president, praise Underfist for saving Halloween. However, they soon discover an army of squid warriors has emerged from beneath the surface, preparing for their next challenge.