The projections of the three heavenly treasures vanished one after another as they fused with Yi Yun.
However, at the moment Yi Yun broke through to the Godly Monarch realm, he knew very well that the three heavenly treasures did not truly belong to him despite having fused with him.
At the end of the day, they were Universe Seeds of this Multiverse, an inchoate form that led to the birth of the next Multiverse.
He could borrow their powers, but he was unable to really take them away.
This was also why the Dao Originator Celestial Thearch had left them behind when he left the Multiverse. They had to stay behind to give birth to the next Universe after infinite time.
But when that happened, with Yi Yun reaching a new realm, he would no longer needed the three Universe seeds.
He would ultimately leave the the Multiverse like the Dao Originator Celestial Thearch to head to a brand new world, to probe infinite unknowns.