Large torsion-powered catapults and siege engines were powerful weapons that could devastate densely packed enemies in open battle, or topple walls during sieges. However, these were heavy and cumbersome machines, requiring large operating crews. Loading and firing took time and left the crew members vulnerable to enemy attacks, particularly from fast-moving cavalry. Placing other units nearby to guard the crew members went some way to protecting them, but arming them and improving their personal armour allowed them to protect themselves.
