For me, the thing that really sucked me into this story is the WORLD.
It's extremely mysterious, imaginative, complex and amazing. Even though you start out knowing very little about it, slowly unraveling it's mysteries is so interesting and enjoyable. It makes me wish I could go there and freely explore it. When I read this story, I can't help but wish there were multiple books set in this world or perhaps an entire MMORPG based on it just so i could spend more time there and learn more about it. This story definitely brought a bit of magic back for me. It's been awhile since I was genuinely sucked into a world and really wanted to stay there.
I like all the old-school RPG themes, like progressing through a journey with a team, where you can buy items and have roles in the party.The idea that there are ranks and puzzles, trials, tests and competitions. A lot of this story involves tests similar to.. for example.. the first ninja exams in naruto. The tests that come up always surprise me, they are very interesting. There's lots of trickery.
Although it incorporates lots of these classic elements RPG people love, it's not really cliche at all and keeps you guessing. The characters are good, there are no fillers, the story is very well thought out and like I said, its not cliche, predictable or annoying like other mangas often get. When reading this story you often get the sense that anything could happen because there's so much left unknown about the world.
Note: At some point on Manga-access, they stop showing the manga as one long scroll down page and start chopping it up into smaller pages and imo it ruins it because frames can get in half between pages, when that happens you can go to batoto where every chapter is one long scroll down.