Simulate Cultivating Immortality, I Have an Extreme Simulator

Wu Wen found himself in a world of immortality where immortals were flying everywhere and human lives were like grass. He had an extreme simulator. He originally thought that he would conquer the immortal world and become the supreme Great Heavenly Lord through repeated simulations. It wasn't until he finished his first simulation that he discovered that cultivating immortality was not as simple as he thought...