Why are the creatures able to finally disappear in the end? Because they touch the Aki's eighths spirit?
And where do they vanish TO? In space? To terrorise another planet?
-------------------------------------
I own you.https://goo.gl/0avZjB
I think that the alien gaya got transformed into a benevolent spirit and since the Zeus canon destroyed earth gaya luckily now the new alien gaya can replace it and both species can coexist on the same planet in peace.
That's my take on it. And about the light beam shooting into space from the new gaya.... I have no idea what it is supposed to mean. Hope this helps a little.