Absolute Necromancer

Absolute Necromancer summary:

Read manhwa Absolute NecromancerThe 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 (spirit master).