Well, Malice isn't the first Naga, and as she said herself, the world is still there. According to Heloise, Nagas bring back old rules, the main one being that there are no boundaries on thought and actions. Any errant idea might manifest in a physical change. Intentions becomes truths without acts.back to Malice.. she will do whatever she fancies, after all. but i do think the predetermination lies pretty much in her being born to end the world..?
might be wrong there, but i think that's her purpose, more or less.
So, it isn't that Nagas are born to end the world, but that by being born, they plunge the world into a state where people are much more likely to destroy it, consciously or not (it would be difficult, but this same power could be use to build a utopia).
So far, we have seen a boy that really wanted to fly grow wings. But what happen when someone really wish someone else to die? I think that's the true nature of the Cataclysm