Everything in this book progresses at a snail's pace. The fights go on and on, the enemies never die, and the main character never leaves his comfort zone to explore anything. I've finished book 4 out of 7, and of the three major enemies introduced so far, the first one died, came back, and almost died again before redeeming herself and joining the good guys. The second one had a few close calls but thankfully died permanently. Except later, the third major enemy comes along. After the whole cycle of almost dying and pulling a couple of ass-pulls, he manages to escape and revives in the body of the second major enemy.
We've barely explored part of the first strata out of the dozens or however many that were mentioned, and as much as I wish we would explore underground some more, I suspect the 5th book is again going to be entirely on the surface. This is all because the fights never end and follow the exact same template: the protagonists get separated, the MC fights, almost wins or almost loses but not quite, and his allies are always on the way but never arrive on time. Then, the fight ends with the enemy teleporting to a new location, followed by an unbearable amount of description before they finally reach that second location.
I will still keep reading because the world is interesting and the overarching conflict of the story is cool, but if it stays like this, it really is such wasted potential.