Story: 10/10
I won't bother giving a synopsis, as the story is too complex for a short paragraph to do it justice.
But what I will say is this:

Most manga authors do not plan out their stories from start to end. If you've every read bakuman, you can see how reviews and ratings often affect decisions the writer makes, causing them to change things on the fly. This often causes plot lines to be dropped, sometimes causing the story to be jerky and inconsistent.

However, currygom is different. Every week, you see readers whining about things, making requests, asking him to insert the main characters back into the plot. But currygom doesn't give a ****. He sticks to his plan, and writes out a beautifully complex, yet consistent story. Sure, readers aren't happy in the short run, but the build up, the foreshadowing, all make for a great story over time.

TL;DR
If a good, well planned fantasy book was written as a manga/ manhwa instead, this would be it. The foreshadowing, build up, and character development is stellar.