Doomsday Chariot: a Three-Wheeled Vehicle at the Beginning, Upgraded to a Mobile Fortress

After three years of delivering express delivery, Chu Xiao didn't even see a glitch in the system. On the day of the zombie outbreak, he was being scolded by his customers. The streets were full of monsters biting living people. His tricycle suddenly rang: "Ding! The doomsday chariot system has been activated!" Chu Xiao thought the moment of counterattack had finally arrived. Until the projection of a little loli wearing bear pajamas popped up and said to him with a sweet smile: "Master~ Your novice gift pack is an alloy Tang knife, but you have to complete ten kills to unlock it~" Chu Xiao looked at the huge tide of corpses in front of him, and then looked down at his rusty tricycle. Silence fell. Is this system just for fun?