Return of the Calamity-Class Death Knight - Chapter 337

A man who was once called the world strongest agent ended up becoming a teacher after his retirement to train the new generation of agents. After many years of training his disciples, he is killed at the age of 60 by the ploy of a secret organization and was reincarnated in another world with all his past memories.Though he was surprised by the magic and the strange species of that world, he adapted very fast to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his tight discipline in order to reach his goal: resume his career as a teacher which he left halfway through in his previous life.This is the story of a man who based on the memories and the experiences of his previous life, became a teacher who travels through the world with his new students.

In a world where summoners wield the power to call forth vampires, elves, angels, demons, and all humanoid creatures from across the realms, Nathan found himself unable to summon beings except from beasts. However, those beasts are not ordinary beasts. They are divine beings who once stood at the same level, if not higher, than the legendary creatures the world ever knew. Casting his gaze to the left, Nathan sees numerous summoners accompanied by the likes of demon kings, archangels, vampire progenitors, and other legendary beings. Turning to the right, a massive army of alien symbiotes is waiting to attack. There was no fear in his eyes, because standing on his left is a majestic wolf who managed to kill a god, the legendary eight-headed serpent coils on his right, above him is the bird who is glowing like the sun, and behind him is a dragon that once gnawed the roots of the world tree. “Let the war begin.”

When necromancers perform a great ritual to summon an undead servant, they bring a powerful vampire into their world. And now, their fate is sealed as food, but for Klaus, this is just the beginning of his adventure. In a cruel world where people will do anything for power and immortality, he is already very strong and immortal, so what's left if not start a family and have fun stepping on arrogant people through the way?

The spiritual energy recovers, others practice, and Xu Bai upgrades.

After getting the game system, because I haven’t received the main mission, I frantically spent 22 years of experience points.

Then……

Xu Bai suddenly discovered that he was already invincible.

Practice exercises.

Full skill.

Everyone: “Why don’t you have a bottleneck.”

Xu Bai spread his hands: “What’s the bottleneck, click to upgrade, isn’t it enough?”

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