Are there any sci-fi novels with profound plots that are not popular and niche that you can recommend to me?

I remember reading a sci-fi novel in 2015 or 2016. It was not very popular, but the plot and content were very profound. I hope that the little brothers and sisters who have read it can tell me the name of the novel. I really want to read it again! I'll kowtow to you guys. Tell me if you know my name. I'll give you a red packet when you go.
Main content:
The protagonist seemed to be a university student, banished to a strange place with a group of death row prisoners.(There seemed to be foreigners among the death row prisoners, both male and female.) Later on, they met the mysterious people. Those mysterious people were originally a group of humans. Later, they became like that in order to fight against the metal species. The protagonist and his party joined their team in order to survive. However, they could only become like them by killing the metal species and putting something into their bodies. That group only had a small territory, almost surrounded by metal. I remember there was a scene where the male protagonist got his ability after killing a metal object. When he ran, his legs turned into a Z-shape. Later on, the male protagonist and his party tried every means to kill the leader of the metal species and escaped to the outside world. It was like a desolate Earth. Later on, the main characters learned that they had tried every means to kill the weakest soldier among the metal species. The level of the metal species seemed to be soldier level, general level, king level, and the most awesome. Later on, the protagonist and his party tried every possible means to return to the real world. Later on, for some reason, the protagonist and his party found out that the place where they were exiled was Earth ten years later. There was a plot where the main character was sucked away during a war, leaving only 1% of his consciousness behind. However, this consciousness became very powerful later on. It could fight against the metal species. In the real world, the metal species had arrived. A mysterious person was fighting against the entire metal species alone. His level seemed to be five Star Diamonds? He died in the battle with the metal species. Later on, she found out that this mysterious man was the son of the male lead. Later on, the king of the metal species found a woman from Earth and "reincarnated" into a human. In one of the duels, the King of the Metal Species said to the male protagonist,"Originally, you were a drop of water, and I was an ocean. Later, you became a river, and I was still an ocean. In the end, you also became an ocean, and I was still an ocean." Neither of us can win against the other. That seemed to be the case. In the ending, the metallic species were actually humans too. They were humans that would be born many, many years later. Because they were too powerful, they had nothing to do and were raised by the AI. In the end, they were controlled by the AI and conquered many planets.
After all, I saw it a few years ago and can only remember this. I hope that my friends who have seen it can tell me their names. I love you and I will kowtow to you.

Answer 1

"Paper Universe: Humanity's New Home" is a science fiction novel about doomsday crisis. It presents the future of mankind in a brand new universe. The story was quite brain-burning and had deep thoughts and discussions. It was very suitable for readers who liked more esoteric science fiction. I hope you like this fairy's recommendation. Muah ~😗