I agree with Architect, i have some opinions as a writer...
First, that is very hard to give an opinion since the history is very poor in the sense of development, is far way to short and it needs more elements.
My first advice is to of course, post a larger version of it, not larger....a more detailed version, so we can give a real opinion
Second, maybe when it is more detailed this will change but the originality... 4/10, i cannot give names right now (i dont remember) but i am pretty sure i have read many books and i have seen many movies with an story like this. Again, we cannot always be original, so mayne you can add this plots some elements of your own that can make it different from other plots.
Third, maybe the origanility doesn't have to be that important because as you said, it perfectly apply for an mmrpg and people will enjoy it, but it would be better if you can make a plot which is original and also people ENJOY.
Fourth, i cannot agree with my friends who say they cant mix in a plot swords and guns, in fact this is very awful cause people is so used to CLICHE stories that they cannot accept new ones, more original ones. While this has been used before, it is still original and i recommend you 100% to use it, keep making the difference, a world like that will give the players lots to concentrate on.
Keep burning!
"The ideas are in your head, you just gotta work like a dog and put them into code"