<p>Here is why I said what I did about Vaatu:
</p><p>We are ALSO told that, should Raava die, we have to wait 10,000 years until she comes back. But they found a way around that. Now, a cynical view on this is that the good guys always get to cheat. But you could also argue that Vaatu could have found a similar loophole, & simply didn't bother to try.
</p><p>As far as the Avatar goes, that is a good point. As far as we know, there is no shortcut to becoming an Avatar--it has to take place during Harmonic Convergence.
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