What happens? Corvo asks, and Cloud has to think about it because he's never actually had to tell this story to anyone before. Anyone he'd bother to talk to about it was part of it, or they already knew, like Zack and Yunlan. But really, there are only a few parts important enough to be worth telling to someone he just met.

"A lot. We failed to stop a meteor from crashing into the planet. And we failed to stop a giant Weapon from destroying the world's biggest city. Only reason the planet's still there is because Aerith helped us from the Lifestream long enough for me to take down the guy responsible. And then..."

Cloud takes another generous sip. "Turns out the Lifestream itself got corrupted, and it infected a lot of people with an incurable sickness. Geostigma. It's how I died."

It's a hell of a reductive and cynical take on what happened, and he knows he's leaving out things people call him a hero for and probably being unfair to all his friends who helped him, but he doesn't feel like a hero. Taking Sephiroth down was just finishing the job he started and cleaning up a mess he made himself, and then it turned out they didn't even finish Jenova in the process. There was a time when he felt good about it, he knows - a time when he felt at peace - but...he can't remember now what that was like.