Dear Master, Dear Master, please allow me to solemnly introduce myself. I am a system, my full name is Purification System. You can call me Xiao Jingjing, of course you can also call me Xiao Hua Hua! Now the world has been invaded by zombies, the end of the world has arrived, and you are the savior of this world! Please wait and drag the oil bottle, weigh the master, make full use of my delicate body, and save the world! !