However, we can infer some things based on their nature and the story:
* Fire: Wargs are depicted as being afraid of fire. This is evident when the dwarves use fire to ward them off while traveling through Mirkwood.
* Humans and Dwarves: The wargs are clearly antagonistic to humans and dwarves, so it's safe to assume they would fear a large, armed group of these races.
* The power of Gandalf: Though not explicitly stated, Gandalf's presence and power are certainly intimidating to the wargs. They seem to recognize his strength and avoid direct confrontation with him.
It's also worth noting that the wargs are not portrayed as particularly intelligent or cunning creatures. They primarily act out of instinct and aggression, relying on brute force rather than strategic fear.
Therefore, while the wargs might be afraid of specific threats like fire and strong individuals, they are primarily motivated by their primal instincts and hunger.