The ascent on the path of the Demon Buddha is incredibly swift, but the flaw lies in its susceptibility to corruption; becoming a demon with a single thought is not an exaggeration.
The fallen monk from the Shi Clan on the Floating Land was evidently an already corrupted Demon Buddha. Although its Demon Buddha Golden Body contained vast Original Buddha Power, it also harbored dense corruption and mutation forces, which couldn't be changed, even when fused with the entire landmass.
If it were just this, Song Chi might not have lost his composure.
The crux, however, lies in the living entity that has walked out anew from the mountain of flesh. Based on the lingering Word Spirit Law around its body, it is undoubtedly a genuine member of the Shi Clan, not an Evil Buddha Clan derived from the happenstance of the Evil Buddha Continent.
"Reincarnation Turning Buddha Skill, huh..."