Absolute Necromancer

" The tower. An unknown place with many rapid changes.Ten years later, I reincarnated into the body of a boy who lives on Earth in South Korea.\"The guy who backstabbed me and the one above him... I'm going to rip into them.\" The person who reached the top as a necromancer and achieved the class above that, Spirit Master Cha Jinhyuk. As the \"All-Master,\" he will take his revenge by climbing the tower as a necromancer."