Are You Still Practicing Cultivating Immortality in the Magical World?

In the world after the immortal cultivators were defeated by the Western magical world, let's see how the protagonist can make a comeback without using cheats. The protagonist travels through time and becomes a slave of the lowest caste, with no system or plug-ins. Outside, the magicians and cultivators had fought to a bloody sea of ​​corpses, but he could only live in a black coal kiln and grow up obscenely. However, when 300 Holy Light Knights came to destroy them, he confidently led dozens of people to meet them! The story tells a world dominated by magic, where cultivators are suppressed. Will the protagonist continue to secretly cultivate immortality and eventually destroy an entire country alone, or will he embark on a completely different path to struggle for hegemony? Please look forward to the subsequent development of the story.