This might be a possibility, what if it is also an auxiliary ingredient in the pill but used in large quantities.
It seemed he had to go to the core sect no matter what, he had to see their missions too.
Now the only thing he had to decide was what way he should take to enter the core sect, his cultivation realm wasn't enough to enter it, asking his master could work, but it might raise unnecessary suspicions, chances were low but never zero.
The third option was through a partner, the best option was senior sister Xie, but if not her, then he had to find another core sect disciple, in fact, if he asked Elder Yan to introduce him to a partner, she would definitely find someone from the core sect to increase his cultivation realm quickly.
It seemed that these were the only options left, he would ask senior sister Xie one last time to become his partner seriously, if she declined it, then he would go to Elder Yan.