I Have a System, That Is, I Am Invincible

Lin Yan was originally a doctoral student on Earth, but he was obsessed with a research. He used his brain intensively and stayed up late for a long time, causing him to suddenly die at home. When he woke up again, he found that he had traveled through time and was selected by the system. With the help of the system, he finally became the emperor and returned to the earth across the long river of time. However, the world was already in trouble and his parents were dead.