When Stan's great niece and nephew come to visit him for the summer, he immediately puts them to work in the Mystery Shack, a tourist trap which overcharges unlucky visitors for a peek at the world's strangest museum, as well as a visit to the gift shop (filled with many "paranormal" objects). In The Legend of the Gobblewonker, Stan decides to take Dipper and Mabel out on a fishing trip to bond with them (As a second reason, he didn't have any fishing buddies because nobody "liked or trusted" him). When the two run off with Soos on a monster hunt, Stan gets rather depressed. When they find out the Gobblewonker was Old Man McGucket's robot, the two (joined by Soos) spend some time with the real "dinosaur", Stan.
Grunkle Stan is a slightly overweight man, with 5:00 aftershave, a pink nose, and gray hair (usually covered by a maroon fez with a golden crescent moon and only seen so far once in Dipper vs. Manliness). When running the Mystery Shack, Stan wears a black suit, a tie, and occasionally uses a number-8-ball cane. When not running the Shack, Stan wears a tank top, and his blue striped boxers. He has slightly yellow teeth, indicating he probably doesn't brush his teeth much.