I've haven't played Halo. My inspiration was more of the
Star Trek variety... Although, I'm sure the concept is similar; big space gun, keeps big bad ships away.
I just added my Star Axis styling to it instead of Cardassian. In this model, the outer hull is the weapon; it rotates around a central spherical core which can float alone like a ship or be docked to a single station block with a basic rail on it. I must say; a google search reveals that the Halo version looks a lot cooler than what's on Star Trek.