Okay, I've read a little over 800 chapters so I think I can give my opinion. 

 This novel is honest, at no point do you expect great depth I think, the MC has few challenges, there are still some, but not in large quantities, only sometimes to add some spice to the plot a villain appears who gives him a slight scare

It's a novel that will keep you hooked for about 500 chapters before you realize that it's already morning and you need to work... I'm not proud of that part... but it's easily one of the best within the "necromancer" idea that I've ever read. 

10/10

There are some problems here and there in the plot, but they definitely all disappear when you have Amaya in the story, waifu 10/10. 

 Definitely one of the best works I have ever read, I really recommend it to everyone who asks about cultivation works, Er Gen is truly a genius