To advance on their cultivation path, cultivators must face countless trials, with the most crucial and perilous being the Heavenly Tribulation. Chen Nan, a prodigious cultivator, has spent four centuries transforming from a mere mortal into a powerhouse, now standing at the Ninth-level Ascendant Realm. Today marks an exceptionally momentous occasion for him. For over 400 years, his thoughts have been consumed by this very day: the gateway to the Immortal-Demon Realm has finally revealed itself. All that remains is for him to conquer this ultimate heavenly tribulation. Yet, even with his immense power and preparation, Chen Nan harbors a deep uncertainty about his success.