DISCLAIMER : I don't own DBZ nor do I have any rights
24 years after Imperfect Cell saga. In this time Cell was never killed by Krillin and Trunks. Future Cell died by Gohan, Kid buu killed by Goku.
Imperfect Cell has finally awaken, having obtain genes from Mystic Gohan, Super Buu, Kid Buu, Super Perfect Cell and he was unstoppable. In fact he didn't even need Eighteen or Seventeen to wipe out each Z fighter. Imperfect Cell flew up and hovered in the sky and prepared a large energy ball, he launched it on Hercule City, leveling it.
Mr. Buu came out furious, holding Hercule's dead body, he steamed and charged at Cell. Cell having obtain Buu's genes used Buu's own Henkai beam turning him into chocolate. Cell ate him and smiled.
Seventeen was in Hercule city that day, he about to buy some groceries because his supplies was low. After the huge explosion Seventeen flew up just to see Imperfect Cell, smirking at him.
"Oh shit" was the only thing that came out of Seventeen's mouth when he saw Cell.
"Don't worry I have no intention of absorbing you, your power is too weak it won't make a difference." After that Cell blew Seventeen up till there wasn't a trace of him left.
Eighteen was using her human eyesight when her cybernetic indicator interrupted her. (it usually happens whenever an enemy arrives, itwarns her for danger.) Eighteen annoyed, looked at the screen to see what it had to say now, which immediately showed her that Seventeen had been killed. Eighteen fell to her knees almost crying. When Krillin ran over and asked what's wrong.
"Its... Seventeen...he's gone..." Eighteen muttered.
"What but how, anyone stronger than him is on our side." Krillin said being shocked by the news.
"I don't know who did it but..." Eighteen continue shaking.
Just then Piccolo voice appeared in their head. Apparently Piccolo was speaking to them using telepathy. The message was heard by every Z fighters and their allies.
"Listen, it's Cell, it seems he survived Mirai Trunks and Krillin attacks, maybe he could regenerate even at his premature form. Now he has awaken in his fully develop form, much more stronger than the Cell we faced." Piccolo said in a urgent voice.
"So what, even I could kill his Perfect form, there's nothing to be afraid of you weaklings." Vegeta said annoyed.
"He killed Majin Buu, and Seventeen already." Piccolo snapped back
"That android boy is weak...But how exactly did he kill Majin Buu?" Vegeta asked now curious.
"He used buu's transmutation beam, is as I feared he had obtain Buu's genetic material..." Piccolo said horrified.
"Does, that mean he has Gohan...Gotenks and all of them too?" Yamucha asked nervously.
"That's a possibility, but what we should be afraid of, is his new regeneration, it's no longer as fragile as a Namek, he has the regeneration of Majin Buu!" Piccolo said in a loud urgent tone.
"Does that mean he have a better more efficient absorption?" Vegeta inquired.
"That's a possiblity, but now is best if you and Goku fuse just in case." Piccolo still just as scared as before.
"Kakkarotto?" "Me fuse with him again?" Vegeta asked angrily.
"Is useless...he has the genes of Vegito as well, no one can stop him." Old kai said blatantly.
Everyone gasped, just then the entire Universe collapse from Buu's Dimensional scream, or should it be called Cell's Dimensional scream. Everything ended there, everyone died, no more heroes. The villains take there very first victory over the Z fighters. No one succeeded, not Frieza, not Mirai Perfect Cell, not Kid buu, not even Gohan Buu, but Cell
Yes I'm trolling LOL