Even with Tang Ye's profound medical knowledge and considerable detoxification skills, he still feared poison. Poisoning someone always happens faster than curing, and during the process of detoxification, the enemy might seize the chance to kill you. Furthermore, poison is unpredictable. If you're too slow or if something unexpected occurs, you'd be done for.
The Poison Technique of Mu Caisang was truly something to be wary of, and it wasn't until he fought with her that Tang Ye understood the full extent to which poison could be utilized. She had refined poison into a mist and used it as a tangible weapon, hiding it in her sleeves, ready to be deployed at any moment. This was incredibly convenient, eliminating any concerns about running out of poison.