The Balloon Spider is a giant spider-like monster made of balloons featured in the film Goosebumps 2: Haunted Halloween.
The Balloon Spider was originally an inanimate Halloween decoration made and owned by Mr. Chu. When Slappy the Dummy brought the spider to life using the Tesla Tower, it began scaring off pedestrians and trapping them in webbing. When Sonny Quinn, Sarah Quinn, and Sam Carter returned home with Haunted Halloween, they found their mother Kathy webbed to a tree. After Sarah loses the book to a bedsheet ghost, the spider snatches Kathy and brings her to Slappy at the Tesla Tower.
The spider reappears during Sarah's fight with Slappy, apparently destroying one of its legs when it tried to stab Sarah. After Sarah triumphed over Slappy, she began using Haunted Halloween to suck in the spider. It was successful at first until the book absorbed Slappy's magic from the Tesla Tower.