Actually, there is many line in perfect work that state only the eye part was found on the Earth
If the Zohar isn't a "gate" to higher dimension, what do you think the "Path of Sephirot" is? Explain me how they pulled the Wave Existence from the upper realm through the Zohar? Explain me the meaning of the word "Zohar" in a context where it's not related to higher dimension. There is speculation and common sense, Xenogears didn't threw all those reference and explanation for us to deduce it was something else. You can argue on the wording if you want, but that doesnt really change the purpose"An unknown "Object" discovered approximately 5,000 years ago. The Eye, which is the main body is said to be a product of an "Over Technology"."
" The "Eye" segment stationed about the upper portion of Zohar's main body is the key element
of the Zohar "device." This mysterious device's structure is, of no doubt, artificial origin.
And even more puzzling, it appears to have been in existence since the creation of our
universe. Moreover, the device is pivotal to the world and story's exposition."
" A certain discovery rocked the modern world-an "Object" with the shape of an eye (though
clearly being of unnatural origins) had been found deep within a bed of sedimentary rock that
was approximately 3.9 billion years old. Eventually, one research institution advanced an
alarming new hypothesis about the "Object," stating that its appearance in Earth's geological
timeline coincided with the earliest known life ever found; the hypothesis suggested this
"Object" may have been the source of all terrestrial life: "artificial" panspermia
(Pan-space embryo)."
The Phenomenon Alteration System, Zohar, repeatedly selects an event with the probability of
zero, while the probability axis continues to incline. At the intersection at which the
phenomenal axis and temporal axis fall parallel, an alternate reality is created; this link
or road is called "The Path of Sephirot." The Path of Sephirot is also the territory of
God and appears, to those who can perceive it, as a watery/wavy place (e.g. the contact scene
between Fei and the Wave Existence).
About chuchu's world, the contradiction come from the fact the Zohar is hinted to be the source of all life, but there was life on another planet. They said it was unhabitable when they left, but life might have survived and evolved again in the next few millions years. Also, XG is suposed to represent Eden, which should be the Earth from a biblical/symbolism standpoint.
Considering every other symbolism were respected carefully (lilith, Abel, protoadam, eve, Cain), it's weird the Eden isn't the Earth.
I already stated in earlier post why I believe they are linked on a level above the "cameo" level. There is too much continuity between both story to not be related.And Xenosaga, really just references some Xenogears points. As much as I wanted it to be linked, they aren't. All the hints and references are just speculation to me, and if that makes you happy, so be it ^^
Yes, Takahashi was planning to rewrite the whole thing from scratch adding new element to it, but it doesn't take anything away from the connection both game share imo,
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