TL;DR - great premise, ******* execution.
I agree on "hidden gem" assessment with other reviewers. This novel definitely stands aside from many cookie cutter xianxia on this site.
As for genre, I'd say it is a xianxia/mystery with a slight transmigration twist.
Now, is the novel good? I am... rather conflicted. On one hand, I read all the 60 chapters available in one sitting and am even so impressed I am writing this review, so its definitely not trash. On the other hand I find myself not adding the novel to my library - after getting a solid taste of what is it like I am just not very exciting for the next chapter.
Writing quality is average. It could be the author is just trying to imitate (poorly written and translated) xianxia novels, and this is causing his own prose to be generic and uninspiring. It definitely has that cultivation aftertaste - phrases like "boundless heavens", "with a flick of wrist" etc. being peppered all over the chapters. It doesn't quite go down to "repeating explanations several times in a row" type of bad, but still there's much to improve in pure technical writing aspect.
For the story, the only good thing for me is mystery. I would honestly like to know how and who is behind the transmigration and fall of Heaven. So, the premise of the story is 5/5, I was hooked from the begging. But again, while the premise is great, the main body of story is disappointing.
Its... slap-dash? Uneven, unstructured. Events just happen, it seems - enemies and allies are revealed spontaneously and just as easily discarded. The tone is inconsistent too - at a certain point it was nearly a slice of life comedy! It definitely feels like the writer is making stuff up as he goes, without deeper consideration - so if the writer isn't caring about his world building, why should I?