In the Rework build, some levels have small Stupid Rats stacked on top of eachother.

Stupid Rat appears playable in a DOOM mod called 'Bring Your Own Class', spitting up projectiles and using various objects like cheese and Rat Balloons to fight demons.

In The Pig City, there are Rat Balloons which look very similiar to Stupid Rat, but are round and blue.

Pizzahead can throw a Stupid Rat during the 2nd phase of his bossfight.

They only exist as a decoration, and don't interact with the player in any way.

In Don't Make A Sound, tiny Stupid Rats can be found, either moving or eating a slice of pizza.

Stupid Rats have a similar function to Prince Froggy from Wario Land 3.

Before the final game, Stupid Rats did not have a bumping anmation and would act as a solid block instead of making the player bounce off.

Stupid Rats appear in some level titlecards and backgrounds.

Gustavo is played as a duo with another Stupid Rat named Brick.

Bowling Pin Rats are called 'obj_obj_rattumble_big' In the files.

Stupid Rats emit a quiet sniffing sound.

There were supposed to be more counterparts corresponding to specific transformations, but they go unused.

These were removed in the Eggplant Build.

In the Rework build, there were still some Stupid Rats which would function that way.

Stupid Rats replaced all of the transformation specific blocks in the Rework Build.It would block the path until the player delivers pizza to a gnome. Before the Rework Build, Stupid Rat had a different function.Pizzascape, Ancient Cheese, Oregano Desert, Fun Farm, Fast Food Saloon, Crust Cove, Deep-Dish 9, Peppibot Factory, Oh Shit!, WAR, The Crumbling Tower Of Pizza (Large) Bumping into a Stupid Rat while grabbing or running will make the player slightly bounce off. Pin stupid rats can be destroyed with the ball transformation (unlike regular ones). Despite being more of a level asset, it adds to combos, similarly to enemies. Stupid Rats block the way at certain parts in a level, and can only be defeated using transformations and projectiles (though not all of them work).

Pin Stupid Rats are similiar, but shaped like bowling pins with two pink stripes. Its small version is the same, except for being square-shaped. Stupid Rats are stupid-looking, rotund, giant ceil-colored rats, with eyes looking at different directions. Rework (Current behaviour, Small, Pin, Small Pin) Stupid Rats are characters and level assets in Pizza Tower.

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