Back then, the Clairvoyant had given each of the Four Divine Monarchs a pendant. The others had used up their pendants during their advancement. Only Lan Jue's Lumina had never been used. Even when he broke through to Paragon, he had never used it.
Though Lumina could not help Lan Jue to recover, it could attract thousands of stars.
Lan Jue's legacy was the Lord of Stars, Emperor Ziwei. Naturally, as its name suggested, the Lord of the Stars could control all the stars, but on the other hand, the stars could also feed Emperor Ziwei. When Lan Jue's protogenia was about to collapse, he was nourished by the power of the stars. He was reborn and straightened out the protogenia. He finally completed his breakthrough and successfully stabilized his realm.