Ghost Singer, I Can Upgrade Infinitely!

[Travel between the inside and outside world, Warcraft alien race, magic summoning flow, skill-based accompanying system (not a brainless system), not brainless, but a cool story, the villain has a brain, the protagonist has an IQ, he kills decisively, please be careful if you mind] The other world invades reality, the rules of the world are subverted, and mankind enters an era where magic is king. Dimensional rift cataclysm! Aliens and beasts are raging! The number of humans has dropped sharply, and they can only survive in the base city! Resources go hand in hand with killing, opportunity goes hand in hand with death! Only by awakening and becoming a hunter can one be able to fight against the monsters and stand on top of the world! Su Chen, the strongest S-level hunter in his previous life, the only special profession of the Nether Soul Singer, can summon countless undead to fight for him! But he spent his only chance to become a candidate for power, and still failed to save greedy and infighting humans. [Voice of the World: Special mission: alert the human race (0/1), failed! [Candidate, I have already said that it is absolutely impossible to rely on human nature. The only one you can rely on is yourself. [There is an opportunity to release the 'candidate's time power'. Is there a restart time? Su Chen returned from rebirth, with part of his memory sealed and his strength returned to the weakest F-class hunter. He could only depend on his sister and barely keep his place in the base city. Having to start all over again, he decided to live only for himself and his sister. Rebind the skill: Voice of the World and become a ghost singer! Infinitely summon souls and infinite upgrades! Giant sword knights, skeletal undead, beautiful fox monsters, divine beasts, demonic dragons, fierce gods and evil spirits... "I am in charge of life and death..." "I am the god!" "This is my army of ghosts!" "Stand up!!!"