In "Sandy, SpongeBob, and the Worm," the Alaskan bull worm is a giant light pink worm with tan teeth and black eyes.
In "My Leg!" it is a darker shade of pink. The worm easily destroys property by eating it.
It is one of the largest creatures in the series, as its mouth is mistaken to be a giant cave, its tongue is mistaken to be the worm itself and its size is large enough to crush an entire city.
Role in series
"Sandy, SpongeBob, and the Worm"
Sandy says she can easily fight the worm because she wants to get her tail back, and SpongeBob unsuccessfully tries to stop her numerous times on her journey. SpongeBob and Sandy arrive at the mouth of the worm to which Sandy mistakes as a giant cave. Sandy enters the mouth and fights with the tongue, which she originally thought was the giant worm. SpongeBob informs Sandy that it is not the worm and that it is just its tongue.
They are later chased by the worm until they happen to lead him off the edge of a cliff where it crushes the newly moved Bikini Bottom.
In this game, the Alaskan Bull Worm appears at the bottom of a pit that SpongeBob falls into while driving, the insides of the Alaskan Bull Worm then becomes a level altogether where SpongeBob meets the Bull Worm's other victims. He and Cannonball Jenkins manage to escape out of the bull worm by making a plane, which starts a flying segment.
The Alaskan Bull Worm appears in the B-Movie nanogame "Alaskan Bull Worm!," where it chases SpongeBob.
During the montage where SpongeBob is trying to purposefully damage Fred's leg, SpongeBob and Fred are standing next to a sign that reads "Stay back!" Fred first sprinkles salt over his leg, then SpongeBob rings a bell and the Alaskan Bull Worm slithers over to Fred about to eat his leg only to stop, sniff, and lick Fred's leg.
Its acts of destruction include eating signs, buildings, SpongeBob's house, Sandy's tail, a fish's butt, and crushing Bikini Bottom.
It is similar to the Graboids, from the Tremors series, which are also giant worms.
The end of the episode, which shows the Alaskan Bull Worm falling off the cliff, also parodies the end of the first Tremors movie.
Sandy's "Worm sign" comment is a direct reference to the Dune book series by Frank Herbert.
In "A Place for Pets," it is revealed that Sandy has an Alaskan Bull Worm as a pet.
Although the worm is large in general, there seems to be a slight inconsistency as to how large the worm actually is.
When first seen, it is easily distinguished as being about triple or quadruple Sandy's height, however, when chasing SpongeBob and Sandy, it seems to have shrunken considerably.
When SpongeBob and Sandy were riding it, the worm seemed to have grown once again.
Lastly, it was large enough to land on and crush the entire city.
Likewise, at the beginning of the episode, it was small enough to travel through the city to eat buildings.