"Then the Lord said, ‘My spirit shall not abide in mortals for ever, for they are flesh; their days shall be one hundred and twenty years.’ The Nephilim were on the earth in those days—and also afterwards—when the sons of God went in to the daughters of humans, who bore children to them. These were the heroes that were of old, warriors of renown."
~ Genesis 6:3-4
The concept of a mythical giant is present is nearly all world cosmologies, folktales, and spiritual lessons. Somewhere, somehow, primeval man contended with, was usurped by, and watched perish the "heroes that were of old." The Hebrew Anak, the Austrailian Yowie, the Sumatran Orang Pendek, the Celtic Fomorian, the Norse Jotun, the Māori Maero, the Greek Titan, the Hindu Rakshasa, the Japanese Oni, the Lenape Allegwi, the Brazilian Mapinguari... look around in nearly any primeval history or mythological account and you are likely to find a reference to a race of giants closely descended from the gods, set loose in their own ambition to lord over men and rule or harass the natural order established by higher creator deities.
Frankly, we are sleeping on the primeval, antediluvian history of our own planet as what is probably the most hardcore Sword & Sorcery setting for our use in game worlds. We're talking occult cabals, spiritual ritual inhabitation, sorcerer-kings reigning in mountaintop garden strongholds, megalithic architecture, time-lost technology, the fuel of heaven for machines on earth, underworld uprisings, and copious amounts of hybrid godlings running amok and creating culture and empire on a whim...
Simon Wong - Artstation
"Impiety increased; fornication multiplied; and they transgressed and corrupted all their ways."
~ Enoch 8:2
So it came to pass that the mighty men of renown, hybrids of the spiritual and mortal, consumed the land, ruled it with unquestioned might, and dominated the mere humans who were their lessers. In all races, across all lands, bound up in the epoch which predated judgment by divinity itself, the giant Nephilim of all stripes reigned and conquered and despoiled humanity with heavenly secrets not meant to be shared.
"And the angels who did not stay within their own position of authority, but left their proper dwelling, he has kept in eternal chains under gloomy darkness until the judgment of the great day..."
~ Jude 1:6