Many trolls featured in the film are featured as background characters and have no given names. Like all the mythical creatures, trolls lived in a world where magic once existed before adapting to modern technology.
In a teaser trailer for the film, a purple troll happily greets a jogging centaur woman who also greets him back.
In the film, one troll is first seen riding on a bike throwing a newspaper to a property. A troll named "Gorgamon" also appears as one of Ian's classmates in New Mushroomton High School where he always puts his foot on the chair to keep him concentrated while some other trolls also appear as students in Ian's high school.
When Ian and Barley go on a quest to find the Phoenix Gem, the two pass through another troll at the border leading to the Path of Peril. Aside from showing a background troll as one of the customers in the Manticore's Tavern, another troll also served as a storekeeper in the Swamp Gas where Ian requests him to refill gas for their van Guinevere but due to Barley's impatience by adding Cheese Puffs and a bathroom key, the total cost increases. Towards the end of the film, a troll can also be seen as a construction worker trying to stop Barley from protecting the fountain.
At the end of the film like all other creatures, trolls continued to adapt when magic is brought back to the land of mythical creatures once again.