Cell explains that he was born by the computer used by Doctor Gero. A long time ago Doctor Gero began collecting the cells of the greatest warriors to research how he could synthesize an android from these cells. However, because it was taking too much time, he gave up on it partway through but the computer continued its operation. Piccolo, Goku and Vegata's cells were collected at the battle when Vegeta first came to Earth. They also obtained Freeza and his father's cells when they came to Earth which explains all the different ki readings. A small spy robot, similar to Cell, was used to collect the cells while also collecting data and sending it to the computer but Piccolo destroyed it during the fight. Even though Doctor Gero's laboratory was destroyed, there was still a small room beneath the laboratory where the computer is. Cell furthermore explains how once he has turned back into an egg he requires three years underground to mature again and that he came back from the future because the absorption of human essence is not enough to achieve his perfect form; it is necessary for him to merge with two essential specialized life forms which the computer told Cell that they were the androids that Doctor Gero has created #17 and #18! In the future #17 and #18 weren't around but luckily Trunks had his time machine so he killed Trunks and came back to his era in search of #17 and #18. The reason why Cell chose this era was because Trunks's time machine already set for this era to warn the other about the androids so all Cell did was push the switch. The computer also told Cell that once he reaches his perfect form, he will have terrible power far greater than anymore imagined. After obtaining all of the information, Piccolo pulled off his shriveled arm and grew a new one. Just when Piccolo and Cell were about to fight Trunks and Krillin arrive. Realizing he has no chance of winning, Cell retreats by blinding them with Taiyoken and escapes to absorb more humans in the direction of Nickytown. Vegeta arrives at the scene and sees that the massive ki reading was Piccolo and when Tien finally arrives Piccolo explains to everyone what he has learnt from Cell. Meanwhile Cell is absorbing the life energy from passengers in a bus and plans to keep absorbing people till his power level is greater than #17 and the others and then he will make them merge with him for unimaginable power.
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