Yes, for the majority that don't know, Immortal Mortal ended in the last week of 2017 with 1253 chapters. The author even post a message on new year's eve saying that he was fine with the ending and liked it, but seeing that I'm doing this you guys can get that I pretty much disliked it. And it's not even about the ending itself, but because the characters end up looking like jerks and the stupid cliches only make this worse.
First things first, Wuji and Cen Shuyin only meet up in the 8th chapter before the end and Yan'Er in penultimate chapter, but because of how the author ended the story they really never spend time together and only to make things worse Wuji and another woman (that confessed to him) spend a night together, making her the only one with development in her relationship with him in the entire series (the best we get between Wuji and Shuyin is a kiss).
2- Despite having several subplots abandoned at least half of them are given answers, although some are disappointing like the one involving his aunt and Aunt Eleven.
3- Although Wuji returned to the Cultivtion World twice and even got back to Earth, he never had gonne back to the Zhen Xing Planet.
4- When he returns to earth he discovers it has only been 50-60 years since he died, knowing that he has about 150 years when he returned to earth and the fact that he spent at least 120 years cultivating leads to the simple logic that the author simply does not understands how the laws of time and space work and he did this only because the he wanted to introduce Wuji's granddaughter to demonstrate that the woman who killed him was really evil.
5- Despite the author mention that Wuji gives much value to his friends and loved ones, he never spent time looking for them, at the end of the series most people who helped him in the final battle wanted to kill him to get his secrets and he even wanted to kill some too, but because they were facing a common enemy they did not attack each other and then because of the collapse of the universe and Wuji with the solution to save everyone they ended up doing nothing against each other.
6- The "Last Boss" of the series appears only around 150 chapters until its end. The only reason he fight Wuji is because of his treasures, which makes him look more like a minion that Wuji had killed thousand of times already. In the end he runs away and the series ends with its "main plot" unresolved.
7- The series ended without we even knowing if Wuji's plan to save everyone in the universe worked out. We don't even have a afterword.
8- Any and all side character that you find in this story is dispensable, they receive between 1 and 5 chapters dedicated to them and are then they are forgotten for the rest of the series. The only ones that don't end up like this are some who want to kill the MC for his secrets and treasures and who have not done so before because of the "villain in the series" or because they didn't find a way to do it without ending up dead.
There are more, much more especially subplots, but I don't want to talk about this anymore. As I said in the comment section in chapter 631, this series IS good, but because the author made so many missteps it end up a disappointing with all it's build up.
Reading the author's other series (the translated part at least) and comparing with IM really demonstrates how the author does not know how relationships ork. Perhaps because he was criticized with people saying the the story was too devoted to the romance that he decided to make it without any romance, which ends up making the characters seem without any depth. (A example of a character opposite of this is Tyrion Lannister in the books os ASOIAF, in which he spend time thinking about his 'wife' and manny other things.)
Even in the part where the MC arrives at Celestial World (A world after the Immortal World) and he gets worried of what will happen to his sect because he thinks that the Immortal Emperor who practically controls the Immortal World will try do to something to destroy it only lasts 5 chapters and after this he has already forgotten and does not even seek to know how to come back to help if there really is trouble.
It's because I like so much this series that I'm so disappointed with it's end. If you like it then continue to read, there will be many good moments in the series, although they diminish with the last chapters.
Final score: 7,5/10