A yo-yo is a toy consisting of a spool attached to a piece of string.
The following tricks were performed in the series.
- Long sleeper: A trick where the yo-yo is kept spinning at the end of the string.
- Parade the pooch, known as let the dog out in the Japanese version: A fancy name Jonouchi gave to the common walk the dog yo-yo trick, where the yo-yo is rolled along the ground.
- Loop the loop: A trick where the yo-yo is spun in a circle around the user's hand, while swinging it in and out.
- Yo-yo murder net (unnamed in the Japanese version): Multiple users surround someone and repeatedly swing yo-yos at them so that they cannot move, without being hit.
- Human hanging yo-yo tech: People are hung by their finger, while it is tied to a yo-yo, which is tied onto something else.
The following yo-yos have appeared in the series.
Jonouchi tried showing off his yo-yo tricks in school, including long sleeper and parade the pooch. However his classmates recognized the latter as him just giving walk the dog a fancy name and laughed at him. In a desperate attempt to impress his classmates, Jonouchi tried performing loop the loop for the first time. He swung the yo-yo in all directions, causing people to run for cover and it resulted in him being tied-up by the string.
Nezumi told Jonouchi to stop fooling around, as he had developed a dislike for yo-yos after being mugged by people using yo-yos as weapons. Jonouchi offered to get revenge for him if he could take him to the attackers. However, Nezumi was secretly working with the yo-yo gangsters and was planning on leading Jonouchi to a trap.
Nezumi took Jonouchi and Yugi to an abandoned warehouse, where they were ambushed by Hirutani's gang. The gangsters trapped Jonouchi in a yo-yo murder net while they hanged Yugi by his Millennium Puzzle necklace from a hook. Hirutani gave Jonouchi the choice to rejoin the gang or watch his friend die, but Jonouchi pushed through the swinging yo-yos, taking several hits and saved Yugi.
By swinging the Millennium Puzzle around by its rope, Jonouchi caught the yo-yos being swung at him on it. He then took the yo-yos, while they were still attached to the gangsters' fingers and hung them from the hook. He called this "human hanging yo-yo tech".
Yugi switched to Dark Yugi and he and Jonouchi split up. On one of the warehouse rooftops, Yugi was confronted by five gangsters. He used his yo-yo to punch a circle of holes in the rusted galvanized roof. As the gangsters cornered him at the edge of the roof, they stood inside the circle. Their weight was too much for the broken roof to handle, so it collapsed inside the circle.
Jonouchi and Hirutani fought on another part of the roof. Jonouchi managed to knock Hirutani off the edge, leaving him holding on by one hand. Using his yo-yo, Jonouchi performed "walk the dog" and hit Hirutani in the hand, causing him to fall.