The Yin-Yang Purple Flame Wolf pack was currently in ethereal form while she was physical. Since the ethereal and the physical no longer existed in the same realm, she could not slaughter them as they were.
If she used the dark attribute, she could indeed kill ethereal Yin-Yang Purple Flame Wolves. However, aside from teaching her how to use the dark element to refine dark spiritual pearls, Ying had not actually taught her how to launch attacks using the darkness attribute.
She believed that all mental cultivation techniques shared common principles, meaning she could naturally use dark spiritual power for direct spiritual attacks as well. But would such an attack have any effect on the shadowy Yin-Yang Purple Flame Wolves behind her?
Chapter 137