Dilemma

Having found the investigative tangent, it would be easier to target the search later. Many things that were previously ignored by other people were discovered by the group, and some information systematically checked out. 

More and more clues affirmed the previous speculation that those who perished here were poisoned. But the rest of the things they found were not as useful. 

The more information they found, the more frozen Mao San Quan's face was, that was because it made them think of more things further into the future. 

Sima You Yue and Han Miao Shuang also thought that if it was the poison from the regular group, it was impossible to have such a severe toxicity that even the Alchemist Guild could not find the cause. Hence, without guessing further, the source of this poison should be from the inner circle.