Piccolo emerged several hundred years later during Dragon Ball, only to be killed by Goku. Before his death, Piccolo reincarnated himself in the form of a son named Piccolo Jr., whom he intended to have continue his mission of world domination, and avenge his death against Goku. Three years later, Piccolo Jr. entered the 23rd World Martial Arts Tournament under the alias "Ma Junior" (Demon Jr). Piccolo fought Goku in hopes of avenging his father and ruling the world, but was defeated in the final round.
Five years later, Piccolo was confronted by an alien named Raditz whose power greatly surpassed that of even Goku's.[4] Realizing the evil Saiyan would thwart his plans for world domination, Piccolo teamed up with Goku in an attempt to stop Raditz from destroying the Earth, and so that Goku could retrieve his kidnapped son.[5] When the two arch rivals teamed up, Piccolo was able to defeat Raditz, and conveniently eliminate Goku at the same time with a new technique that he originally intended to kill Goku with, the Makankosappo (Special Beam Cannon). During the battle, Gohan had revealed an amazing hidden power, and Piccolo knew that it would be useful against the two other Saiyans that would be arriving a year later. It is also later revealed by Kami that Piccolo sensed his upcoming death against the approaching Saiyans, and that his attempt to train Gohan would've resulted in him gaining a successor.After being defeated by Android #17 and Android #18, Piccolo seeks to unite with Kami, and gain another massive increase in power. After uniting with Kami, Piccolo becomes aware of a more dangerous threat named Cell, even more powerful then the androids who had defeated him and the others earlier. Before his second encounter with Cell, Piccolo once again battles the androids, except this time he battles #17 one on one. After a somewhat even match, Cell arrives on the battle scene and needing to absorb the androids to complete his power, Cell attacks and Piccolo attempts to thwart his plans to gain power. Piccolo is nearly killed by Cell, and he is forced to participate in a Martial Arts Tournament created by Cell called the Cell Games where he fights one of the seven Cell Juniors that are created by Cell, who are later destroyed by Gohan. During this time, Gohan surpasses Goku and defeats Cell, saving the Earth from total destruction.
Seven years later, Piccolo acts as a trainer to Son Goten, Goku's second son and Trunks ,Vegeta's son, and their fused form Gotenks. Piccolo trains the boys in fighting the evil creature Majiin Buu and he later gives his energy to Goku's Super Spirit Bomb, which Goku uses to defeat Buu once and for all.
In Dragon Ball GT he is severely injured by Gohan while he was possessed by Baby and later dies with Earth in order to destroy the Black Star Dragon Balls. He goes to Heaven but then requests he is sent to Hell in order to free Goku when he is imprisoned there. He can be seen putting Hell in order and protecting the rulers there. In the final episode, Goku stops in Hell to see Piccolo. He tells Piccolo that he will be leaving and that they are glad they met and teamed up. He also says that he has become a good friend and he will get out of Hell someday. They shake hands and Goku leaves while Piccolo stays behind.
:Masenko-Ha
:Hellzone Grenade
:Grenade Fire
:Renzochou energy-dan-dan
:Gekiretsu Kodan Light grenade-ha
:Regenaration
:telepathy
:Nemik fussion
Piccolo: Even with the energy you took from me, my power is still far greater than your own.
Piccolo: Not bad, for an early prototype. (talking to cell)
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Piccolo: [Talking to his split form] Hey, make a mental note - tails grow back
Piccolo: I've never had real feelings about anyone before... Grr... I don't like it!
Piccolo: Fool! Never believe anything the enemy tells you!
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Piccolo: We can't give up just because things aren't the way we want them to be.
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Goku: What did that Shin say to you? He wasn't rude was he? Do you want me to set him straight for you? I bet if I told him you were once the Guardian of Earth he'd have a little more respect!
Piccolo: No! Don't do that! Please! Don't do anything! Please don't!
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Piccolo: My ears do more than just frame my face.
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[Piccolo and Vegeta sit back to back on a tiny island]
Piccolo: Is it over?
Vegeta: Not until the fish jumps. [a fish jumps out of the water]
Vegeta: It's over.
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