Immortal Emperor Fei with the help of Deep South Divine Emperor originally built the Celestial Academy in the corner of an Ancient World, then pulled its spatial area from this world to a plateau in Arrogance. The academy returned to this ancient world, weakening its defenses and forcing its ancestors to stabilize its coordinates.
Soon the other members of the Celestial Academy realize the arrival of enemy forces wanting to seize the treasures of the academy, some quite openly, others still hidden. The enemies decide to wait for the perfect model, when the power of the ancient world dragging the academy in became increasingly stronger.
The first wave of attacks was started by Winged-Oblivion Demon Emperor together with the Grand Emperors of his Clan, Immortal Emperor Bai Lian and an entity described as a Lion-headed Man, controlled by an Alliance of 14 Immortal Monarchs led by Freesky Immortal Monarch and including all the other 4 Monarchs from Freesky Sect and the 3 Monarchs from Rumination School. Realizing the involvement of the Sacred Teacher, Li Qiye, Immortal Emperor Bai Lian retreated, but other Immortal Emperors still joined in on the side of the attackers, while the Immortal Monarchs and Emperors affiliated with the academy declared their stance. Finally, Heaven Authority sent a decree, representing the will of the three races regarding the Celestial Academy:
“It is time for the emperors of the heaveners, devils, and diviners to band together to destroy the academy. May our three races prosper for an eternity!”.
The Battle included three of the four 12-will Emperors, namely World Emperor, Profound Emperor and Immortal Monarch Yi Ye. The latter two left to engage in a private skirmish, seemingly leaving the Academy at a disadvantage. Nevertheless, World did not attack directly but left the forces under the command of Darkness Heaven Emperor and his Celestial Court. They used their trump card, the Cosmic Immortal Carapace, to counter the High Heaven Palace controlled by Li Qiye, but were not able to gourd against his Primordial Will, losing control over the Carapace. This forced World Emperor to take action, who battled Li Qiye and Mortal Reversion Ancient God, using a copy of himself created by the Qian Clan. World commanded Darkness to initiate the Peacebringer Art in order to kill Li Qiye, but he was able to counter with a Heavenly Execution, thus revealing yet another enemy, Brilliant Devil Emperor, who already fell to the Darkness and was only used as a vessel by one of the strongest Overlords of the current era.
His appearance was accompanied by the opening of a portal, but the other Dark Overlords did not join the fight due to Li Qiye's World Seal-self threatening them with the Primordial Light. With the return of Yi Ye, the fight over the Academy culminated in an all-out battle between the Dark Overlord and the team of Li Qiye, Mortal Reversion Ancient God and Immortal Monarch Yi Ye. The Academy side revealed the possession of an Immortal set of Armaments and a piece of Primordial Lightstone, while the Dark Overlord used the Death Coffin and an Paragon Aritfact - True Bones. The battle was decided by Hong Tian using her Emperor Suppression Art to halt the retreat of the enemies.
The other Grand Emperors and Immortal Monarchs were held captive by Li Qiye's Heavenly Execution, and World Emperor traded the life of 9 of them (including Darkness and Sword Emperor), for a copy of his Heavenly Scripture. The rest of the Emperors were executed with their Heaven's Wills absorbed into Li Qiye's Primordial Will. The Academy was declared the orthodox lineage of the hundred races, leading to a period of peace. The involvement of Li Qiye was intentionally left unmentioned, such that the fame for the successful defense of Celestial was attributed to Immortal Monarch Yi Ye and Mortal Reversion Ancient God.