Reborn: I Open Blind Boxes in the Apocalypse

This is a world shrouded by a black sun. On the day the apocalypse began, a solar eclipse suddenly appeared in the sky. But after the sun turned completely black, almost all electronic devices soon stopped working, plunging the entire world into darkness. The sun never returned to normal after the eclipse. It remained black. Then black rain began falling from the sky. Creatures touched by the black rain seemed to be infected by a virus, gradually turning into zombie monsters. Humans... turned into zombies too, though a small number were different and did not mutate. And among that small group, a tiny fraction not only avoided mutation, but awakened instead. They awakened supernatural powers: fire, lightning, ice, immense strength... When Chen Yun woke up, he discovered that he had transmigrated into the apocalypse in his sleep and awakened a very unusual ability: opening treasure chests. The contents of each chest are random. If you can think of it, there’s nothing it can’t contain. Hey! Isn’t this basically a blind box?! (This story takes its time. The protagonist doesn’t immediately crush the heavens, the earth, and everything beneath them. He grows stronger gradually, and he’s no saintly hero, but a flawed, flesh-and-blood person.)