umbaba said, 'Enkidu, what you have spoken is evil: you, a hireling, dependent for your bread! In envy and for fear of a rival you have spoken evil words.' Enkidu said, ‘Do not listen, Gilgamesh: this Humbaba must die. Kill Humbaba first and his servants after
Humbaba reminds me a lot of Goliath, and since he tried to trick Enkidu, maybe cunning like the devil.
he heavens roared and the earth roared again, daylight failed and darkness fell, lightnings flashed, fire blazed out, the clouds lowered, they rained down death. Then the brightness departed, the fire went out, and all was turned to ashes fallen about us. Let us go down from the mountain and talk this over, and consider what we should do
I thought this might be an early representation of the devil or evil, with horns and fire. Although it could have contributed to later representations of the devil or hell, it might have just showed how great a deed the two did in killing Humbaba. The scale of what they did might have made an impact in how greatly they were seen though in the descriptions of Uruk at the beginning of the story, so maybe it starts to show the impact of one or two people, like some kind of savior?