Medicine King Summit.
This was the only summit in the Formless Blade Sect without 'sword' in it's name. It was also the summit that Yan Qianyin was staying in. It's said that the the Medicine King Summit used to be blossomed with spiritual ingredients. However, after time, it became like the other summits, where the spiritual ingredients were planted by the cultivators.
When Mo Wuji entered the foot of the Medicine King Mountain, he was immediately stopped. It was an ingredient girl who wasn't even 20 years old.
"Greetings junior apprentice sister, I'm Mo Wuji from the Lotus Sword Summit. I've specially come to see senior apprentice sister Yan. Please help me inform here." Mo Wuji knew that in the entire Formless Blade Sect, only his Lotus Sword Summit was without defences. It wasn't because he didn't need it, but because he didn't have the power to install any.