The magical artifacts around which the entire series is based, the Dragonballs. They were first introduced to the story when Bulma encounters a weird monkey-tailed boy named Goku, tricking him into giving her his four star Dragonball, which his adoptive grandfather Grandpa Gohan, has left him. From that point on, the Dragonballs became a permanent fix to the story and many threats surfaced with the Dragonballs being the desired object.
 Creating the Dragonballs
Creating a set of Dragonballs requires an enormous amount of skill and sorcery. This level of skill was only possessed by a very specific group of Namekians, members of the so called "Dragon Clan". Throughout the series, only three Namekians were stated/shown to possess the ability to create Dragonballs, namely Kami, Guru and Dende. Connected to a set of Dragonballs is a magical wish granting dragon. In the case of the Earth's Dragonballs, this is Shenron, and Porunga for Namek's set.
 Bond with the creator
After a set of Dragonballs has been created, they, as well as their respective dragon, remain closely tied to their creator, and his faith. The dragon for example, cannot grand wishes that exceed the creator's power. Example: Shenron wasn't able to destroy the Saiyans Nappa and Vegeta when they were on their way to Earth, simply because their powers were greater than Kami's (creator of the initial set of Earth's Dragonballs). Also, when the Dragonball's creator dies, the Dragonballs instantly turn to stone and can no longer be used as a result.
 Summoning the Dragon
In order to summon the dragon, not only must one gather all seven Dragonballs, but they must also summon the wish making dragon by performing a chant. To summon Shenron, simply saying "rise Shenron" for example, will suffice. But in the case of the Namekian Dragonballs, the chant must be performed in Namekian language.
 List of Dragonball sets, requirements etc
Following below is a summary of every Dragonball set featured throughout the series' entire run. Also listed are the creator's, requirements and all other relevant information:
 Earth's Dragonballs (1st set)
- Creator: Kami
- Dragon: Shenron
 Namek's Dragonballs
- Creator: Guru
- Dragon: Porunga
 Earth's Dragonballs (2nd set)
- Creator: Dende
- Dragon: Shenron
 Black Star Dragonballs
- Creator: ???
- Dragon: Red Shenron
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