Whilst Chen Piu was too busy dealing with the Void Splitting Slash, Tang Yin utilized the Heaven Deceiving Art to make himself appear as if he was seriously injured.
He did not want to expose his power. And by acting as if the Void Splitting Slash was his full-powered last-ditch effort to kill Chen Piu, he completely sold his story.
Without hesitation, Tang Yin turned around and 'fled'. He had already bought a couple of minutes for Elder Liang and Elder Zi. Battles between high-level cultivators usually transpired for less than a minute. A few minutes should have been sufficient for them to come up with a result.
Tang Yin had 2 plans based on the potential outcome of Elder Liang and Elder Zi's battles.
If they managed to severely wound the black-cloaked people, he would help out in any way he could without revealing his true abilities.