Cultivating in a Demonic Sect with my System

Li Feng found himself in a dangerous demonic sect where he could be killed at any moment. But he was worried as he had his ultimate upgradation system.Blood Essence Pill -> Blood Origin PillTurtle Breathing Mantra -> Xuanwu's Great IsolationPhantom Spirit Fox -> Nine Tailed Celestial FoxJust like that, Li Feng was confident that he would be able to become stronger at a very fast pace and would be able to survive in this dangerous demonic sect. Not only that but as his parents were killed by some of the disciples of this demonic sect, he was also going to take his revenge on them. With his system's assistance, Li Feng was confident to reach the pinnacle of cultivation.