The barrier between the Human Realm and Underlands, better known as the Demon's realm.
At the end of the war, when the demons knew their loss was inevitable, they launched a full-out attack on the helm.
Not caring at all for the survival of their species, millions of demons flooded the human realm, simply trying to kill as many people as possible.
Seeing this, one brave hero sacrificed his life and all his magic force to create a mountain range between the Human and Demon realms to prevent the demon's relentless attacks.
Do you know want to know what the mountain range was called?
Named after the hero who sacrificed his life, the mountain range was named the "Hajin Range."
Yes... the very mountain range I went to as soon as I transmigrated and discovered the Dragon's Eye in.
Quite the throwback... is what I would be saying if I wasn't panicking.
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