A groan escaped her lips as her mana pool began to drain rapidly. Her brows furrowed, and her body soon began trembling from the sheer scale of what she was attempting.
Isaac looked down at the city and was surprised to see that Catherine had already covered nearly three-quarters of the Sky City. The city itself was not particularly large compared to some of the other places he had seen, but concealing an entire structure in such a precise manner was still an extremely complicated task.
What impressed Isaac even more was that Catherine could already use evolved Aura to modify her skill to such an extent. He felt proud when he saw her progress, but at the same time, there was a faint ache in his heart whenever he thought about how she had reached this point.
