Imps are humanoid beings of various sizes, and appearances, some of which possess magical powers which they use for their own purposes. They are often associated with goblins because they have a mischievous reputation. They resemble short humans with pointy ears, although a few rare imps may have rounded ears like a human and their most common skin color is green while some imps may share the same skin colors as humans. Imps have very varied sizes compared to other races seen, with some being the same size as Smurfs, while others are the size of short humans (but seeming like giants when compared to the more common smaller imps). There is also a different variety of imp known as Miniature Imps which are even smaller than regular imps and grab on to certain people they like to the point where they might not ever let go, and it is almost impossible to remove them due to their impressive strength.
The Smurfs first encountered a nameless imp in "Smurfette's Dancing Shoes" when he sought to marry a fair maiden in order to get his hands on the ancient Treasure of the Trolls. He forced Smurfette to make her marry him by using the magical dancing shoes he had given her that she could never take off. Papa Smurf, however, saved her by using magic words he found to remove the shoes from Smurfette's feet and placed them on the imp's feet and those of his guardians.
Another imp by the name of Dr. Charlatan paid the Smurfs a visit when he was chased out of a human village for selling a worthless "miracle tonic". The Smurfs were duped into believing the fake doctor's promises of the tonic, almost to the point where he had captured them and planned to use them to make up an actual miracle cure for every known illness. Papa Smurf had stopped him from doing so by tricking Dr. Charlatan into believing that he had contracted an illness from the Smurfs that required a "miracle cure" from Papa Smurf. The said "miracle cure" that the village leader provided, however, had ended up curing the imp of his lying.
A third imp character is Dismal Boggs, an adventurer whom Grouchy comes across in his attempt to escape celebrating his birthday party in "The Secret Of Shadow Swamp". Dismal was searching for the Enchanted Falls where there is a hidden secret paradise, and so the two join together in the search as Papa Smurf and a team of his little Smurfs also go into the swamp to search for Grouchy.
In "Smurf A Mile In My Shoes"; an imp simply known as The Cursed Imp (because he was not given a name of any kind during the time of his appearance) was once a handsome round-eared imp who had been transformed by the Sea Witch into an ugly cursed form due to his mischievous ways. Before he was cursed, he would play pranks on anyone, including other imps, but he changed his ways after being cursed and would devote his life to making friends after being freed.
In Papa Smurf's flashback story in "Papa's Family Album", an imp named Hotap used goblins to kidnap all of Papa Smurf's little Smurfs when they were Smurflings, with the exception of Brainy who managed to escape. He was intending to turn the captured Smurfs into gold when Brainy temporarily stopped the imp's machine with his book, giving Papa Smurf enough time to appear with his magic powder to duel with the imp and cause his machine to go backwards, destroying itself in the process.
The Game Master is an imp who challenges various people he comes across to a game where the loser ends up becoming one of his game pieces. In his encounter with the Smurfs, though, his final challenger Grouchy used one of the Game Master's rules, "wizard takes all", against him by using Papa Smurf, who was both a Smurf and a wizard, to remove all of his opponent's pieces from the board, thus freeing all the people from their imprisonment and sending the defeated Game Master home crying to his parents about losing.
In "Papa's Last Spell", Papa Smurf performed his magic before an audience of esteemed imp and elf wizards.
In "Vanity's Closest Friend", a Miniature Imp (that was about half the size of a Smurf) named Winky appeared - he was Vanity's quickly accepted and even sooner rejected best friend. He did not leave Vanity's side until the end of the episode where he switched over to Gargamel.
In the "Smurfs Monsters" comic story "Motro, the Forest Monster", an imp that was working for some human bandits aided them in destroying Mother Nature's Smurf park garden and when the Smurfs proved troublesome, the imp summoned his forest monster, Motro to capture them in order to sell them to Gargamel.