Extinction!

"Modify Glory City? It's not impossible, but it will consume a lot of my essence, to the point that I will need almost a thousand years to recover afterward. Moreover, the process will take a long time." 

After feeling around the Atlan Dimension, the Mother Tree answered with a sigh. Due to the size of the dimension, it would not be possible to delegate the task to other Tree Folks. Only the personal touch of the Mother Tree could successfully modify the Atlan Dimension. 

Despite the challenges mentioned by the Mother Tree, Merlin heard the implicit meaning in his words. While the Atlan Dimension was indeed huge, if the Mother Tree decided to modify it, he would definitely succeed.