Adds a cannon mounted turret and specific cannon shell magazine ammunition that behave like the tank shells without friendly fire colliding. Bonus technology to make all walls and gates resistant to explosions to better works with the cannon turret.
Adds barbed-wire, which can be placed down and hurts and slows down any enemy that walks on it.
They can be upgraded to:
Reinforced (more health and damage)
Slowing (slows down more)
Conductive (can be powered to deal extra damage)
or any combination of the three.