This is the second series. Unlike Dragonball, which was comical, Dragonball Z turns serious. It start with revelation from Goku's long-lost brother that he is a Saiyan, a breed of super warriors with superlative abilities and power that Goku has never imagined. He soon realized that he prefers to fight for justice and not for destruction like Saiyans. Ultimately he protects his friends and Earth from the terror of the Saiyans and much more powerful foes he encounters here on Earth and on distant planets. He eventually prepares his son, Gohan to become a much powerful fighter. With the help of new friends and the Dragonballs, Goku defeats great monsters, androids, and magical beings that want to destroy Earth.
Chaozu has the power to communicate telepathically or stop people in their tracks. He is small in size and has a bright white complexion. Tien and he are the best of friends. His originality is unknown which makes it more questionable. He shows great potential in the Dragonball series, but later on, doesn't increase much in power, so he is not able to train and keep up with the Z Warriors.
He is the first son of Goku. He is trained by Piccolo after the battle with Radditz where he showed his potential power. Eventually he looks up to Piccolo as a role model. He even wears similar clothes.He has the potential to be the most powerful being in the universe, but he can not completely utilize his strength. This strength is showed when his hidden powers are released by anger. He later learns to go full potential without showing much signs of anger. He is the first saiyan to reach SSJ-2.
Goku is the main character of the Dragonball sagas. He was sent to Earth as an infant to prepare it to be sold, but he fell into a ravine and hit his head when he was young. He then helps out to save Earth. He is not too intelligent, but he is very good a the martial arts and can also can use Ki. Goku by far has the most abilities of any of the Z warriors. He marries Chi-Chi, daughter of Ox king; and together they have two sons, Gohan and Goten.
Goten is the second son of Goku and Chi-Chi. He and Trunks spend most of their time together, and are very good friends. Goten exhibited high power when he went Super Saiyan at the age of 7. He bears a very strong resemblance of Goku. Goten is usually happy, but has a habit for throwing tantrums to get something he wants.
Gotenks is the result of Trunks and Goten performing the fusion dance. Gotenks has a tendency to over-dramaticize the situation, and makes up names for all of his attacks. Since he is young and naive, he believes that he can defeat anyone. Most of his assaults are incredibily stupid and ineffective, but he'll squeeze in a few that do some damage.
Krillin is the most powerful human on Earth, although his abilities are still dwarfed by Goku and Gohan. He was once Goku's rival when they were young, but they later became best friends. Since he is a Buddhist monk, he shaves his head by choice, although #18 convinces him to grow some hair later in the series. Krillin is willing to sacrifice his life for Earth (and he has). Whenever possible he is at Goku's side.
Pan is Goku's granddaughter, and she is Gohan and Videl's daughter. She is 1/4 Saiyan and the most powerful female in all of Dragonball. Pan is very adventurous, and can get into trouble, usually with Trunks and Little Goku. Trunks, Goku, and Pan go everywhere together. She is the little sister they never had.
Piccolo is the offspring of Piccolo-Daimao from Dragonball. Like his father, his intentions are evil, but when a greater evil, Raditz, threatens the Earth, he turns to the side of good and helps Goku. He later trains Gohan, and the kid help Piccolo become a good, well-meaning person. He has very powerful attacks and is capable of regenerating body parts and manipulating his size and shape. Piccolo is a formidable fighter.
Tien is the second strongest human in Dragonball. He is about Goku's height and pretty muscular. He has three eyes, two normal eyes, and one eye on the top of his head. Tien is good friends with Chaozu, and is his bodyguard. He is also a good friend of Goku. He is the developer of the technique known as the Solar Flare (a fantasically bright like that is formed by fanning one's hands across their face).
Trunks is the first child of Vegeta and Bulma. He is 1/2 Saiyan. There are two Trunks. Future Trunks comes from a alternate universe 14 years in the future where the evil Androids 17 and 18 rule the Earth. He goes back in time and, after killing Freeza, he warns the Z warriors of the coming arrival of the androids. So as not to prevent his own birth, he tells no one of his heritage, except Goku.
Little Trunks is born between the death of Freeza and the arrival of Androids 19 and 20. He likes to hang out with Goten and they are very good friends. When Goten and he are together, he has a tendency to get them in trouble. Trunks is also sad that he does not have a brother like Goten. Trunks has purple hair and displays extreme levels of power. He reaches Super Saiyan when he is eight. Despite Trunks' ability to get Goten and himself in trouble, he means well.
Vegita is the Prince of all Saiyans. Born on the planet bearing his own name, Vegeta has the bloodline to become a super-elite Saiyan. He was a henchman of Freeza. He is regarded as one of the greatest fighters in the universe. Along with Goku, Radditz, and Nappa, Vegeta is one of the only Saiyans to survive the destruction of their homeworld. He is extremely jealous of Goku's superior fighting ability, and actually helps him from time to time so that he still has someone to compete with. Vegeta craves nothing more then ultimate power until the very end of DBZ.
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