Give the Era of Swords and Magic a Touch of Immortality Shock

He was originally an invincible demon king, but because of his many evil deeds throughout his life, he was jointly sealed by the world's immortal cultivators. It took the Demon Lord thousands of years to break through the seal. At this time, the era of immortal cultivators had long ended. What greeted the Demon Lord was the era of swords and magic. (Don't read it as a cool article, there may be a knife in the future, so be careful!)