the so called human Dragon skull found in China

[Ninurta]

To add to prior post.

Then we have the pictures (not many) of our Giants or Masters and humans. 

Notice the 6 opium poppy seed pods sticking up out of Inanna's shoulders, 3 on each side, and the opium poppy she holds in her right hand. How better to enslave someone than to get them hooked on opium? The "Earthlings" shown there appear to be not just any old Earthlings, but Elamites - what would be classified today as "Iranians". They may instead be Habiru - desert dwelling nomadic raiders from the west of Sumer (from the deserts of Saudi Arabia and Syria). What they are not is Sumerians.

But could this also be pictures of our Masters with their Pets!!?? Yes, their human creation are their Slaves and Pets.

That appears to be Gilgamesh wrestling with Enkidu on the right, when their brotherhood was born, and, on the left, Gilgamesh and Enkidu fighting the forest spirit Huwawa in "the Cedar Mountains", which I presume were in Lebanon ("Cedars of Lebanon"), which marked the beginning of the end of their brotherhood, as Enkidu was made sick by the vapors Huwawa breathed out, and he sickened and died. The death of his brother Enkidu was what prompted Gilgamesh to go off on his disastrous search for immortality.

In the center appears to be Inanna, but it may be Gilgamesh's mother, the goddess Ninsun.

After Gilgamesh and Enkidu fought, Enkidu was transformed from a "wild man of the waste lands" into a full human. That process was started when Gilgamesh sent a temple hooker out to "spend time" with Enkidu in the wild lands, and after she had her wicked way with him, the rest of the animals shunned him. That narrative does seem to fit into your idea that humans were transformed into humans from animals that already existed here.

A bit of linguistic trivia that has a bearing on this discussion, especially relevant to these engravings: in the Sumerian language, the word for "king" was "lu-gal" Lu-gal, literally translated, means literally "the big man".

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