Return of King Arthur - Catapult Vehicle Design

This is a Design Process Principle project, the story for this concept is a fantasized version of the black death plague that happened in the 14th century in which the disease evolved into a deadly virus that caused the infected people to turn into deadly creatures that hunt for people. In the darkest time, the brilliant King Arthur has returned from his eternal rest to protect the kingdom. At the brink of collapse, the catapult serves as a defensive weapons that are able to deliver projectile attacks as well as charging at high speed to eliminate whatever that is ahead of it.