Trunks comes from the future bearing bad news in the Cell saga, he predicts the coming of the androids. All this is after he kills Frieza and King Kold. Everyone is surprised that he is a Super Saiyan, especially Vegeta, since all Saiyans are supposed to have been killed by Frieza. From a chaotic future, Mirai (Future) Trunks comes back in time and kills Freeza bot, along with his father, King Kold. He warns the Z fighters about his future, and tells them how they can prevent any of it from happening. In Trunks' future, two androids, Numbers 17 and 18, are wreaking havoc across the globe. Surprisingly, he can also become a Super Saiya-jin, making him the second (in our timeline, that is) to become one. This really pisses Vegeta off, who later finds out that Trunks is his son. When he goes back to his timeline for the second time, he finds that history had not changed. But he is a lot stronger so he kills androids #17, #18, and even Cell.