Irwin suddenly creates chaos in Endsville while trick or treating with Mindy. When he decides to open a certain door to a certain house a host of evil events take place. Irwin and his friends heroically try to battle these forces, thus giving birth to the team Underfist.
Underfist: Halloween Bash
Irwin, Hoss Delgado, Jeff the Spider, Fred Fredburger, and General Skarr from the "Grim Adventures of Billy and Mandy" team up to fight an evil candy army from the Underworld on Halloween.
