Damn guys maybe this is getting a little heated. I don't know if we can definitely say what the mural is unless you know of something in an ultimania and even then it might not be true to the original game.

I'm starting to think they accidentally used the spell once and that's what brought Jenova. After they finally sealed Jenova, they found where the knowledge of how to summon meteor was concentrated, and sealed that away as well...

Quote Originally Posted by Wolf Kanno
Its a weird anomaly in the plot, which is a shame cause almost everything else is actually well thought out.
I am bookmarking this!!!