Piccolo Daimao conflict
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
The birth of Piccolo Daimao
Roughly 300 years before the start of the Dragon Ball anime, the Nameless Namekian was given the opportunity to become the Kami of Earth. However, the current Kami at that time felt a horrible evil lurking deep within the Nameless Namekian and would not allow him to claim the throne until all of that evil was expelled. The Nameless Namekian meditated and, in 461 Age, found a way to use a technique called Fission which would expel the evil within him. However, when this evil was expelled, it manifested itself into the being later known as Piccolo Daimao. The Nameless Namekian, who now called himself Kami, could only watch as Piccolo Daimao began a reign of terror over Earth that would result in the deaths of thousands of people.
In an attempt to take control over Earth, Piccolo Daimao created several offspring. He ordered his children to attack and destroy Earth's cities and kill all of the people. The killings went on for some time until they eventually attacked the dojo of Mutaito. Though these skilled and powerful martial artists were able to fight and kill a few of Piccolo Daimao's minions, this battle came with a hefty price. Only two of Mutaito's students survived the battle, Muten Roshi and Crane Hermit, and they narrowly managed to destroy the remaining minions. Piccolo Daimao himself soon arrived on the battlefield, and before Roshi and Crane Hermit could even attempt to attack him, he used his Finger Blast to send them flying. Eventually, Mutaito stepped in and saved Roshi and Crane Hermit only to also find himself heavily outclassed by Piccolo Daimao's horrible power. Defeated and left to die, Mutaito was taken and nursed back to health by his two surviving pupils, and went on to continue his training alone in the mountains.
Several years later, Mutaito reunited with Roshi and the two headed out to find Piccolo Daimao for the final confrontation. They found Piccolo Daimao in the ruins of a city where Mutaito wasted no time revealing his new technique, the Evil Containment Wave. Using an Electric Rice Cooker specially designed to trap evil, Mutaito launched the wave and successfully trapped Piccolo Daimao in the jar. As a result of performing such a powerful attack, Mutaito died, but not before telling Roshi to throw the jar into the deepest ravine he could find. Mutaito then died and Roshi fulfilled his final wish by throwing the jar into a very deep ravine.
The effects of the Piccolo Daimao war were cataclysmic on Earth. Thousands if not millions of people were killed and hundreds of cities and towns completely demolished. Some of the greatest martial artists and other warriors were also killed off, leaving only those such as Roshi and Crane Hermit left to defend the Earth, and subsequently take on pupils of their own. As centuries passed and Earth's population began to rebuild, the story of the Piccolo Daimao war became nothing but a fairy tale.
King Piccolo Saga
Main article: King Piccolo Saga
Almost three and a half centuries after the end of the Piccolo Daimao war, the evil Pilaf somehow managed to find the jar containing Piccolo Daimao sometime during the 22nd Tenkaichi Tournament and was able to successfully release him in hopes that he could team up with Piccolo Daimao and conquer Earth. Upon his release, Piccolo Daimao had naturally grown old and decrepit from spending so many years in the jar, and he soon afterwards spawned Piano to serve as his attendant. Sometime later, Pilaf told him about the Dragon Balls, which Piccolo Daimao decided to obtain in order to wish for his youth back. As a result, Piccolo Daimao made his first order of business to eliminate all of Earth's most powerful warriors so that he would not be opposed. In order to do this, he spawned Tambourine, whom he sent out to the Tenkaichi Tournament Arena on Papaya Island to steal Son Goku's Four-Star Ball and list of all of the fighters. Tambourine arrived just after the tournament had ended, so he simply stole the list of fighters, but not before killing the young Krillin, who had attempted to stop him from taking Goku's Dragon Ball. Goku and the others soon arrived to find Krillin dead. Goku then decided to track down Krillin's murderer. Using the Dragon Radar, Goku chased down Tambourine only to be easily defeated due to his exhaustion from the tournament earlier that day.
Goku later met Yajirobe, who killed another of Piccolo Daimao's offspring, Cymbal, after he attacked them for Yajirobe's Dragon Ball. Goku eventually killed Tambourine and finally came face to face with Piccolo Daimao himself. After putting up a decent fight, Goku was eventually defeated by Piccolo Daimao and appeared to be dead. Roshi, Tenshinhan, and Chaozu eventually attempted to stop Piccolo Daimao as well. Roshi attempted the Evil Containment Wave, but accidentally missed when transferring him into the jar. Roshi died as a result of the move and all of the Dragon Balls were stolen. Piccolo Daimao then summoned Shen Long and wishes for restored youth. Chaozu attempted to stop him from making his wish by calling out one of his own, only to be quickly killed by Piccolo Daimao. After making his wish, Piccolo Daimao also destroyed Shen Long and headed for the castle of King Furry.
Sometime later, Goku recovered at Karin Tower and retrieved the Ultra Divine Water which greatly boosted his power. He arrived to find Tenshinhan alone and trying to stop Piccolo Daimao by himself, but was mercilessly beaten by Drum, another of Piccolo Daimao's offspring. Goku saved Tien and killed Drum, and finally set his sites on Piccolo Daimao as well. After a long and epic struggle, Goku finally killed Piccolo Daimao, but Piccolo Daimao played his final card. He spit out an egg containing his reincarnate, Piccolo. Piccolo Daimao then died and all was returned to normal. Goku eventually met with Kami, who agreed to resurrect Shen Long. After Shen Long was resurrected, a wish was made to revive all those who had been killed by Piccolo Daimao and his minions, including Roshi, Kuririn, and Chaozu. Goku then spent the next three years training with Kami and Mister Popo, preparing himself for battle at the next Tenkaichi Tournament where he would face Piccolo Daimao's reincarnate. Piccolo's Daimao reincarnation, Piccolo, ultimatly turned good and joined Goku in protecting Earth. Piccolo also maintained Piccolo Daimao's connection to Kami which allowed the Dragon Balls to continue to exist until Piccolo and Kami fused and a new Kami had to be chosen. Piccolo then sacrificed himself to save Earth and traveled to Hell to keep the villains in line after helping Goku escape.