What if Sephiroth won?

[Waggle6points]

Albeit I'm new to the game's extensive lore and all this forum stuff. But I had a lingering thought in my head after I beat the game. "What if Sephiroth did become a god?" Would the whole planet be wiped out? The lifestream disbanded sorta? Obviously I'm guessing cloud and party would die, but what would Sephiroth really, do? He would have completed his whole journey, but for what? Even if it's said in the game and I missed it, would be great to get an answer, thanks y'all!

 

[null]

That’s basically all there is to it. He’s insane. He wants to screw with Cloud and be the next Calamity from the Skies, in that order. At the end of the day he’s just a dog chasing a car, like The Joker, except with less self awareness.

 

[Nanaki Skywalker]

I think Advent Children shed light on the full extent of Sephiroth's next move in the event of him winning (though this was connected to another plot altogether); basically, as soon as Sephiroth pulled a Shang Tsung on the Lifestream, whatever was left of the Planet would then become a meteor set on sailing the cosmos and landing on the next unfortunate planet, as Jenova did 2000 years earlier, and the cycle would repeat itself.