A powerful spell was certainly a good thing.
But the greater its power, the more mental focus and cultivation it consumed, rising with the tide.
Maintaining a spell at this level was a tremendous test of Su Shi'er's cultivation.
The rolling heat waves formed by the vast swathes of earthly fire erupting from Tai Chi Gate swept indiscriminately in all directions.
Naturally, Su Shi'er himself was the first to bear the brunt.
And as the earthly fire merged into Purple Cloud Surging Waves' sword body, the spell's power continued to grow.
Su Shi'er had to expend even more cultivation and release more of his Primordial Spirit to sustain the spell, ensuring it could continue without spiraling out of control.
After all, if a spell of this magnitude went out of control, there was no way he could escape.
Losing half his life would already be the best possible outcome.
More likely than not, he would die on the spot!
Only because Su Shi'er's cultivation was profound, and because his Primordial Spirit had recently improved further, could he manage it.
If either had been lacking, he would already have been unable to control this powerful spell.
As Su Shi'er pushed his cultivation with all his strength, Ling Yue Shang steadied her own breath and turned her gaze toward him.
"What a Daoist Tianshan. I thought his earlier move had already been the limit of his strength."
"Who would have thought that he could borrow the earthly fire and lava from the fire-element formation region to bolster this fire-element spell to such a degree!"
"The power of this move would not merely contend with cultivators at the peak of the Spirit Severing stage. Even a great cultivator at the early Body Integration stage would likely not dare take it lightly!"
"One must