|First Appearance||Season 7 ("Tis The Season To Be Smurfy")|
Gustav is a human toymaker that Grandpa Smurf and Sassette encounter in their visit to a human village on Christmas Eve in the cartoon show special "'Tis The Season To Be Smurfy". His craft is in the making of puppets which he hopes people will buy for their children on Christmas. However, seeing that had no customers on that particular Christmas Eve, he proceeded to go home to his wife Elise until a young boy named Hans stopped him, showing interest in his toys. Pleased with the young boy, Gustav gave Hans one of his puppets as a gift. However, the boy's father scolded him for consorting with poor people and threw the puppet underneath his carriage only to be trodden down, saying that he will buy Hans finer toys than what Gustav could make him.
As Gustav arrived home, the doctor who was watching over his wife told him that her condition was grave, that there was a possibility that she would not last beyond that Christmas. Gustav tried to cheer up his wife with tales of "Christmas elves" that could make wishes come true, but Elise tells him it will take more than wishes to make it a merry Christmas. Gustav joined his wife in bed as they rested, hoping that by morning Elise will be strong again.
Unknown to Gustav, his situation was being watched by Grandpa Smurf and Sassette, who decided that they should do something to cheer up him and Elise. They returned to the Smurf Village, hoping they would get help from the other Smurfs, but as they were all preoccupied with preparations for their Christmas, Grandpa Smurf and Sassette realized they would have to take matters into their own hands with only Wild Smurf to help them. Fortunately, Papa Smurf had returned from his visit to Homnibus to get his little Smurfs to start thinking beyond themselves and rescued Grandpa Smurf, Sassette, Wild, and Chitter from being buried in a blizzard while they delivered their Christmas decorations to the elderly couple's house.
Although the Smurfs had successfully decorated Gustav and Elise's house without waking them up, an accident caused by Clumsy had awakened Gustav, who then saw that his house was full of "elves". He awakened Elise so that she could see for herself, and the couple were so astounded by what the Smurfs had done for them, Elise felt herself getting stronger, and Gustav rewarded them by giving Sassette one of his toy puppets. However, at that point Hans' father was tracking down someone who stole his bag of gold with some guards and the trail led to Gustav's house, that, when he saw how it was decorated, made him assume that Gustav had stolen the gold and thus had him arrested. Elise tried to come to her husband's defense by saying that it was elves that decorated her house, but neither Hans' father nor the guards believed her. Fortunately, the real thief had shown up confessing that he was the one who stole the gold and has returned it to its rightful owner, thus clearing Gustav's name.