The Lawnmower was an ordinary lawnmower that somehow came to life and was possessed by evil.
It is unknown where the Lawnmower came from. All is known is that it is alive and chases and possibly "eats" people. However, it is unsure if this is the same lawnmower from Monster Mower or that this is another family member.
During Harry Potter and the Awkward Movie Crossover (...For No Reason), the lawnmower appears while the cast of Harry Potter is having a conversation. They scream when they see it coming, but it is unknown what happened to them.
Later, Mario and Luigi are about to battle Bowser and Kamek when the Lawnmower shows up. It chases the Mario Brothers away until they bump into Julian Petruzzelli, who is filming an episode of Smashing Stuff. Because it interrupted his show, Julian decides to smash the lawnmower with his sledgehammer instead of an iPhone as scripted. Mario and Luigi shortly after thank him. ("Act I Part 4")
- The lawnmower was from another series by Richalvarez called Monster Mower which has been "cancelled" due to no one watching it.
- In Episode 9, Bob mentions the Lawnmower as part of a great video game he created.
- Before the lawn mower appears, the movie hints at its appearance by having him being mentioned in the Youtube News segment, including interview footage with Richie & Chris in the same clothes that they wore in the Monster Mower series.