The Stay-Puft Marshmallow Man is a fictional character from the Ghostbusters franchise, who sometimes appears as a giant, lumbering, and paranormal fluffy monster with a big cute but also creepy looking smile on his face.

After images of him are seen on an advertisement and a bag of the marshmallows earlier in the film, he is then seen in the climax of Ghostbusters as one of the physical manifestations and forms of Gozer, a god who is defeated when Stay-Puft is destroyed.

The likeness of Stay-Puft was inspired by Peter O'Boyle, a security guard at Columbia Pictures whom Reitman met while filming his previous movie, Spacehunter: Adventures in the Forbidden Zone (1983).

According to Sam Delaney of The Guardian, "Stay-Puft's familiar mascot combined elements of real-life brand ambassadors the Pillsbury Doughboy and Bibendum (a.k.a.

Ray Stantz (Aykroyd) instead makes the decision to think of this marshmallow mascot when the Ghostbusters are given a choice as to which physical form Gozer will destroy the world in.

The plan triggers an explosion that destroys the gate and Stay-Puft, reducing the latter into molten marshmallow cream that rains down onto the roof of the skyscraper and bystanders on the street below.

The character is also briefly visible in an ad on the side of a building (a matte painting) during the scene where the Ghostbusters headquarters roof explodes.

Stay-Puft has the ability to spawn Class 5 Manifesting Outworlders, labeled "Marshmallow Minis" that vaguely resemble Gozer's minions Zuul and Vinz Clortho, to do his bidding like overwhelming the Ghostbusters.

This causes Ray to admit he had not selected such a bad destructor after all due to it having strategic disadvantages; as demonstrated in the film Ghostbusters (1984), a gargantuan Stay-Puft Marshmallow Man is too slow because of its weight and lack of bones, and had less offensive capability beyond its massive size, therby making Gozer vulnerable to proton streams and boson darts fired by even just one Ghostbuster when under this form.

In comparison, Gozer's Destructor Form is weaker than Ivo Shandor's, which is much faster and agile, and, while in the Ghost World, can charge itself with spiritual energy to make itself stronger, taking five Ghostbusters with every upgraded arsenal that they have to defeat.

[18] In the realistic version, the player can listen to one of the in-game answering machine messages from an upset member of the fictional company that owns the Stay-Puft Marshmallow brand (voiced by Chuck Huber), who is unhappy with the recent Gozer/Stay-Puft attack, believing it was a publicity stunt by the Ghostbusters.

Stay-Puft's role as a hundred foot tall rampaging monster is replaced by the sketch ghost from the Ghostbusters' logo who was morphed into a giant-sized version of itself assumed by Rowan North, the film’s antagonist.

Tiny-sized versions of it (labeled as "Mini-Pufts") make their appearances as Gozer's mischievous minions for purposes of sabotages, deceptions, and distractions.

Like Gozer's Destructor Form, they look funny, adorable, seemingly innocent and, additionally, harmless in size (each is 3.5 inches (89 mm) tall) on the outside.