It's just a vague theory at this point but I think that the Master of the Valley didn't build the castle and wasn't the original master of Toriko and the others. The mirror (which has the heads of the beasts on the handles) is clearly made to be used by someone human sized. Since it was hidden away in a sealed room and set into the sarcophagus, I'd say it hadn't been used in a very long time. The Master of the Valley didn't need the mirror to control the beasts and his soldiers relied on fear to tame them (the eyes). The many statues and such in the castle in the shape of the beasts make me think that whatever civilization lived there held them in much higher regard than the Master does.
There is probably some connection between the Master of the Valley and the sarcophagi since they're both inexplicably found in freezing rooms. I don't know if we'll ever know what that is though.
Exactly what I think. Well, as these games leave several blanks in their lore, I prefer to interpret them and fill the gaps as I please and make my own story out of it. So let's discuss our made up stories filling the gaps and, maybe, get one crowd-thinked canon out of it, taking care of what is shown by the game itself. Or at least let me explain my own headcannon.
So, these ruins are human made and ancient. The master of the valley thing is a foreign entity made of magic or from another world or an ancient evil or whatever, but as it looks to rely on technology and not (or not only) on magic, I'd say it comes from another world rather than just being a god or demon.
For the villagers, being a chosen one is not a good thing necessarily, imo. It's just they understand they need to get rid of some chosen kids (or people) to be left alone for some time by the tricos. It's like the lady the dragon takes from time to time in several other fictions. A sacrifice so the dragon is entertained for some time and doesn't destroy the whole village.
The barrels are processed butterflies, at least in my mind, and the kids only feed the master of the valley alien thing. It's like a parasite that invaded the place, ended the humans and set up the mind control to have the tricos as its own guardians. The guardians are bad because they protect the evil master thing. Trico (our Trico) is "the last guardian" because he ends the guardian thing by taking the boy to where he destroys the antenna and the master. But not Trico really, as the last one really should be the last one who is still mind controlled, and Trico is the first one being non-controlled. Because he learns that the boys can be helpful and lovely, but I don't understand why he isn't controlled when the big antenna starts running. I thought it could be because him not having the headgear anymore but no, because he gets controlled anyway in the smaller antennas. That's a gap I still have to fill.
Anyway, the other Tricos, they don't die in my mind. They have awesome healing capabilities as seen on Trico, so even if they fall from that high, they should be cured later. Trico survives that fucking feast they made on him, so...
The "ivory" tower could be made by the "alien" master thing. It's different from the rest of the ruins, and it's still flawless. But then the mirror shield works on it and seems to be made by/for humans. Could be another thing.
At the end, there's 4 eyes indeed (I didn't notice until someone said it here) so that feeds my headcannon that Trico goes home (because they lived once there with the humans, until the thing came to control them and use them to exterminate the humans, plus their own armors now controlled by the thing, too). Proof of this is that there are trico statues over the ruins, some destroyed, because they are ancient from times where the humans revered them as godlike or something really helpful probably. Sooooo, I derail lol, Trico goes home to rebuild his tricos society and he gets a family with her girlfriend which is the other pair of eyes shown after credits. Maybe it's the reason why he hasn't go visit the Boy when he's older, because otherwise it's mean of him not paying some visit. Clearly the boy can't get there, it's Trico who has to make the trip, right?
Gonna comment further later but feel free to discuss or add or substract from this headcannon.
Also still have to comment on my favourite and most touching scenes, later.
