Counterattack from Villain Boss to Savior

When he woke up, Xu Xian tragically discovered that he had traveled through the background story of a doomsday zombie game - Rising Sun Siege. What's even more tragic is that it even wore it on the villain's boss. How to fix this? Are you just waiting for the protagonist group to come and destroy you and save the world? Etc! This timeline... Xu Xian was surprised to find that the time he traveled through seemed to be before the villain's boss turned black. What's even more surprising is that the system is also awakened! Bite! The disease transport system has been activated... Disease transport? What the hell kind of system is this? … In the previous story background, I wanted to be a good person. But in the current backstory, I am the savior! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.