Heaven and the Elven Empire are the most technologically advanced groups outside Humanity in the LDC. And for the last
8,000 years, they've used swords, spears, and arrows. Humanity used those for less than a third of that time before moving on to bigger and better weapons. Think on that.
The long-winded explanation?
Evolution of Warfare is the ability to identify cause-and-effect and apply it to combat. Whenever the holder comes across something new, they are capable of rapidly gaining a workable understanding of whatever it is and applying it to various things. Gunpowder for example: Elves have known of it's existence for roughly a hundred years now but they have yet to move past "it explodes when exposed to flame". A human took a look at it, and went "I can use that."
Eleven hundred years later we're doing shit that's scaring Divine Beings.
Or, in simple words: the scientific theory. We're capable of a thought process that no other species in the LDC is capable of despite numerous dumb-down explanations we've given about it. They haven't worked it out yet regardless.