I didn't say he DID use it, dude. I'm aware that it's one of his attacks, as I am of all others that belong to the villains in Final Fantasy. In gameplay Sin's Terra Graviton creates tunnels in the Earth and nukes areas on it; the party seems fine afterwards. Look at Eden's attack. It nukes part of an alien planet and the Earth. The party seems fine in-game as the FFVII party do after Supernova. Do you see that these things could've happened to the party but didn't so that there can be a good ending?