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According to the content of the book, humans classified the strange constructs of this world into four tiers.
The lowest tier, also known as man-made constructs, can be mass-produced as long as there are blueprints and raw materials. They can be utilized based on human needs, like the steam train in front of us now.
This was what had puzzled Chaoyang before—as a steam-powered machine, its locomotive's design was indeed delicate and compact, and its stopping and starting were quite flexible, highlighting a level of technology that seemed out of place with steam engines. Now he understood; this device was just a construct that looked like a steam train.
Moving up, things humans could not create were next.
For instance, Third Class Oddities, also known as arcane divine artifacts, ranging from dozens to thousands in number, could be utilized by humans but could not be replicated in their essence.
