The best characters are without a doubt the magnificent Lord Fifth, the most dignified furry lover under heaven and the almighty meat patty, Ultimate Vexation, that is able to even cause the mightest of cultivators to suicide.
Let's start with the basics. This novel is almost a rip-off of Martial God Asura. The similarities between them are ridiculous, and we can link thousand of things. Firstly, the cultivation system is almost the same, and the method to go up a realm is identical. Then there's also the fact that both main characters are ruthless, smart and handsome. The difference? Yun Che knows medical things and doesn't r*pe girls like Chu Feng. By that point alone, I believe that Against The Gods is better than Martial God Asura. A remastered version, if you will. Then, there's also the fact that Jasmine is basically Eggy, and many other thing.
Anyhow, there's still more. Remember the banquet arc of Against The Gods? 'The Battle That Shook New Moon City' arc? Well, just a few days ago, Martial World began a new arc (It begins around 365). It's also an exchange of pointers, and the other powers bully the sect or clan the MC belongs to. Even the battles are almost the same, specially the first few ones, with the reactions of the people who lose and the elder exactly the same. However, it must be noted that Martial World is finished, and over 2000 chapters (2253 to be exact). The author has already begun another series, True Martial World, which is 524 chapters long so far. Against The Gods is only 676 chapters long at the moment. It's obvious who thought of the idea first.
Now, let's continue our analysis. There are many other elements, but I'll speak of another who which made me angered. You guys remember the arc in which Chu Yuechan was injured, and Yun Che had to take care of her? Yes? Then, isn't the similarity between it and the arc in Battle Through The Heavens where Xiao Yan takes care of Yun Yun (Or whatever her name was) rather uncanny? Again, Battle Through The Heaves is already finished, with 1648 chapters. It's more than obvious who came up with the idea first.
Also, Yun Che uses a heavy sword. Xiao Yan uses a heavy sword.... how strange, don't you think?
There are also many other similarities between Against The Gods and other series, but I won't go too much into that. There are also many cliches used: Yun Che has a mysterious past, he gets a legacy left behind by someone, and a peerless master in his head. The only different point is the fact that he has some superb medical skills, but he rarely uses that anyways.
Anyhow..., what I mean to say is that Mars Gravity is a great author. Superb, even. However, he could really use some originality. In my opinion, he would be better off writing fanfiction or something.... Anyways, if you haven't read other Xianxia and Wuxia, Against The Gods is a great place to start, as it's amazing. As long as you don't have previous knowledge of other novels, that is.
However, if you're looking for more originality, and much less cliche, along with an amazing plot and everything else, then, well.... You should give World of Cultivation a look. It starts slow, but I can say that it, along with I Shall Seal The Heavens, are the best novels I have ever read. I'm not talking about Xianxia and Wuxia Novels... I'm talking about ALL kinds of novel. They are simply amazing in every single way. Martial World is also an awesome novel, and although it's rather cliched-ed, I believe that it's pretty good, much better than Against The Gods and Martial God Asura, at the very least.