Breaking Through the Calamity

In this world, immortal cultivators have not been able to summon heavenly tribulation - a challenge one must complete to ascend to immortality. Lu Cheng, a transmigrator, has unfortunately been used by his sect master to help him ascend as he is the only one that can attract tribulations. At a dying moment, he finds himself with a system at hand, and every time he receives a tribulation, he levels up.