400 Years of Cultivation? What Happened to Being Born Invincible!

Traveling to a different world, others are busy fighting monsters, upgrading and picking up girls. Fortunately for Lin Cheng, he was trapped in the cave as soon as he walked through. What should I do if I can't get out? Just practice. After practicing for four hundred years, he accidentally became invincible. After being rescued four hundred years later, he decided to follow his savior out for a walk. So, the whole world panicked—— "Where did this monster come from?!"