The Grandmaster Strategist - Volume 5, Chapter 22: A Raging Inferno Burns the Fortress

In a world where human and monsters relied on mystical fruits and their inner power to fight for dominance, a lost soul was thrown, given the powers from all the other worlds he’s known. But there was a catch; he had no control over what power he would get! With knowledge beyond that of most, he sails his path to the top of the one piece world!

- Description from Novelupdates

Yeon-woo had a twin brother who disappeared five years ago. One day, a pocket watch left by his brother returned to his possession. Inside, he found a hidden diary in which was recorded “By the time you hear this, I guess I will be already dead….”

Obelisk, the Tower of the Sun God, a world where several universes and dimensions intersect. In this world, his brother had fallen victim to betrayal while climbing up the tower. After learning the truth, Yeon-woo decided to climb the tower along with his brother’s diary.

“From now on, I am Jeong-woo Cha.”

On a normal boring day, a message appears, inviting him to a Tutorial.