There were a few novels where the protagonists obtained the Four Celestial Slaying Swords or the God-Slaying Spear. They were "The Wilderness: The Immortal Cultivation of the Whole Clan, Triggered 10,000 Times Return","Closed Door Meditation for a Hundred Years, Obtaining the God-Slaying Spear at the Beginning","The Wilderness: Reward the Four Celestial Slaying Swords on the First Day of Registration","Attracting Hatred Begins from Douluo", and "The Wilderness: Becoming Zhu Bajie at the Beginning". These novels were all fantasy, xianxia, or fantasy immortal cultivation. Some were related to the primeval era, some were related to the Journey to the West, Douluo Continent, and so on. I hope my recommendations can meet your needs. You are also welcome to share your favorite novels with me. Muah ~