Quote Originally Posted by sora_lion_heart View Post
With Sephiroth Weakened, Cloud goes to fight with him some more when Sephiroth stabs him through the stomach. Sephy says "don't push your luck" and cloud with adrenaline picks Sephiroth up and throws him off the edge. So it was Sephiroth that got thrown off the ledge not Cloud.
There is also the version where he jumps into the Lifestream of his own free will. The amusing thing is that the Ultimania mentions there was two different ways that scenario went down and it doesn't actually specify which is canon.