General Duanmu's Journey to the West

Multiple protagonists, Journey to the West, time travel, fusion of worlds. General Duanmu, while hunting Okuser, is sucked into a black hole and arrives in the Journey to the West world just in time for Sun Wukong's imprisonment under Five Elements Mountain. He then accompanies the Tang Monk and his disciples on their journey. Tang Monk: "Wukong, why did you kill them?" Sun Wukong: "Master, if we don't eliminate the evil, they will harm the good!" General Duanmu: "I can't be bothered to reason with you; you don't deserve to listen. Once a demon (villain), always a demon (villain)!" Then Tang Sanzang is trained by General Duanmu and becomes Tang Sanzang (actually a time traveler who was pretending all along, enjoying playing the fool). Tang Sanzang: "This holy monk will bury heaven, earth, and all beings! Disciples, pull out the weeds and roots, search carefully!" Sun Wukong: "Jade Emperor, get down! The emperor's throne rotates; next year it will be mine!" Demons: "Run for your lives! The demon-killing machine General Duanmu is coming to eat us!"