I think that the story writing style is pretty well written, although the start didn't really awaken my interest that much. This is pretty good for a first time, however I think that you can do a bit different style of starting the story, so that we get to know the characters and terms better. It would for example be better cool if you could describe the appearance of the three enemies in and described mana with other words. The beginning is pretty well but I think this kind of story would make a bit more sense to be started "in medias Res"(it starts in the middle of the happening), and it would make the story more exciting.