Kenshi/Swordsman [Game fan] [No system] [No heroine]
The First Empire: It had the most advanced civilization technology, but it collapsed for unknown reasons
The Second Empire: Catron and his followers rebuild the empire, trying to recreate the technology of the past. As time went on, Catron became more and more brutal. Phoenix, the leader of mankind, the strongest warrior in Oakland, and the holder of the eternal flame. Overthrowing the rule of Catron and his followers, a new empire was rebuilt, one of the oldest in history.
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Modern times: The birth of Phoenix Sixty-Two, the Red Rebellion, the destruction of Buster City, Lukin's revenge, the birth of the swamp, the overthrow of King Shagel...
There are many races here, advanced technology that no one understands, and slavery in feudal society. If you get beaten here, you can become the strongest in the world!
The protagonist is reborn as a slave in the Holy Kingdom and comes to this wasteland continent with technological gaps.
Become an assassin in the shadows, a thief with great wealth, or a warrior in his own right.
He began to lead his own team and build his own empire...