Strictly speaking, the novel of fixing truth belongs to the oriental fantasy system and has nothing to do with western mythology.
The realm in Xiuzhen's novels mostly refers to the realm nouns in the ancient system of cultivating immortals, in which "Na" and "Yuan Ying" are neither material nor intangible. Spells and magic weapons are partly borrowed from classical novels and partly created by themselves. So there is no need to be too entangled.