Umm, I have some "fears" about the continue...
Two ideas popped in my mind, but I hope I will wrong.
1. All the prophecies tells me that maybe someone went back in time and create all the stories the children went throught! The one who wrote down all the puzzles, prophecies and made the bulidings, traps, and all! Maybe the very end of the story they find a time machine and one of the children (or maybe all three) go back to the time of the Mu and Atlantis. They will be the ones who create all the prophecies... About the dark eyed girl who arrive the Galapagos, the Book of Seven Languages, and god knows what else will they still find.
And that's why they made the medalions especially for the two children!
2. One of the Golden Cities is on the Moon. In the 2nd season 1st episode we saw a picture in that temple where Mayuka went, and there was a triangle. Maybe the top of that means the seventh cité is high in the sky.
These two things I'm afraid of the most and don't want to see... I think I would hate if they find a time machine OR a space ship
-Zia- I think Zia also a child of the Sun. She just never tried to call the Sun, and maybe she could do it!
Why else is she a chosen one? We never seen any special skill of her (like Esteban who can summon the Sun...) Okay, she can heal and get along with animals, but it's not that kind of special skill...
-The medallions- Maybe they will work only for children under some certain age! Maybe under 14 or under 18, or so. (Just like someone can't go to Narnia after a certain age...
) That's why Esteban's father couldn't use his medalion! So Esteban and Zia should have hurry!
-The cities- Maybe the cities can regenerate themselves! One of the "holograms" told that the cities are aternal (or something like that). So maybe none of the cities really destroyed. They just "felt" that some "persona non grata" stepped in, and the defensive mechanism started to work, to chase away the intruders (They talked about this defensive mechanism in the 1st season!). Maybe some time later the cities appears again with their full beuty.
-About the triangle again, which we seen in the first episode on the wall of the inca temple. Another idea of it, that the position of the cities. Maybe it pictured the Earth. So if you "put" that triangle on the world map, maybe the points of the smaller triangles spots the cities... So one in Yucatan, one in Tibet, we knows about. Others points at: The north pole (Grönland?), the south pole, north-west Australia, and one points the Pacific ocean(where the Mu continent supposed to exist ) and one in the Atlantic ocean (where Atlantis supposed to exist).
-One thing I really like to see!
Zarés or Ambrose singing the sailor song!
By the way I've read someone mention that he swallowed some orichalcum. Maybe his boussole can detect him now?