Billy's pet hamster, Mr. Snuggles, celebrates his 10th birthday, so the Grim Reaper comes for him. However, Mandy, Bi...

Billy's mother, Gladys, first notices Grim in Billy's bed, then in the shower and subsequently starts to get panic su...

Billy and Mandy tell Grim it is "Opposite Day" and that, when they say something, they really mean the opposite. Due ...

Grim is bored of being left alone while Billy and Mandy are not with him. Grim decides to fulfill his dream by workin...

Grim misses his life as the reaper of souls and, due to his bet, he cannot return to the Underworld, much to the hila...

After watching a movie, Grim teaches Billy to possess people by jumping into their heads. Billy possesses Mandy and m...

Billy wanders into a junkyard, where a massive hole in the earth opens up and pulls him down in. Later, Mandy and Gri...

Billy, Mandy, Grim and Pud'n are part of the "Person Scouts" (a Boy Scouts-esque organization) and need to sell cooki...

While Spring cleaning in the middle of November, Billy takes an old, cursed lamp from Grim's trunk. When he gives it ...

After having a nervous breakdown and leaving the house in the first episode, Billy's mother, Gladys, returns. She mee...

With Irwin not answering the phone, Billy's parents missing and Mandy saying she wants "Billy for dinner", Billy and ...

It's Halloween, Billy, Mandy and Grim go trick-or-treating. Grim mistakes a woman for Atrocia, the host of the all-ni...

Nergal, the fiend from the center of the Earth, returns to the surface, emerging a carnival with him, trying once mor...

Billy tells Grim to help him throw a surprise birthday party for Mandy. Then, a reluctant Grim helps Billy prepare a ...

Billy and Irwin have been playing their favorite video game, Beasts and Barbarians, for three days non-stop. In an at...

Billy, Mandy, and Grim go to the museum on a school trip. There, they meet Hoss Delgado, self-appointed hunter of the...

While going to the shopping mall with Billy and Mandy, Grim spots the beautiful Eris, the goddess of discord and chao...

Billy eats too much junk food that makes him feel sick. Grim prepares him a remedy using his granny's recipe, but thi...

Billy is constantly provoked by a bully named Sperg and runs over to Grim for help.

After taking the Underworld's "Bad Book" from Grim, Billy becomes possessed by an evil entity. Then, Billy steals Gri...

Mandy and her parents leave the city for a day, which makes Billy feel lonely. Then, Grim uses his supernatural power...

In this musical episode, which pays homage to Little Shop of Horrors, Billy befriends a singing brain-eating meteor (...

Billy, Mandy, and Grim eat moldy pizza leftovers, and after falling asleep, they have nightmares. Billy dreams of cut...