I was mind blown when I read it the starting is very typical ok... the shit gets real in further chapters I really like how the MC is very powerful but is not invisible or cunning like the trash MC in the chinese manhua. Plus idk what but the Korean writers just know how to make a great MC.
So demons and stuff will appear to like in the world of the previous owner of the sword. I mean it seems a bit weird for him to just be waving his sword around like that.