\
Assets for another project that I don't imagine will see the light of day here.
Its basically equal parts drydock, jump-gate and mass-driver and serves as a system's primary method of defense, able to through precise calculation even strike objects in the atmospheres of other planets with specialty torpedo munitions that guide when approaching target or disintegrate if they miss and strike something from behind similar to shrapnel. Formerly known as the Star Fortress Null, capturing it was a turning point in a major war that granted a system independence as its jumpgates were purposefully severed or shut down or the guarding of the openings was increased exponentially.
The thing is caked in regolith and its composed of eight massive towers and a central hardlight rayshield that contains an atmosphere, acting as a special "true" drydock ships can enter through. The gravity control grants that ship to become its own down-vector so the occupants can get out and walk on it without falling off and conduct surface repairs or sunbathe on it and appreciate the view.
Null uses nuclear detonations in the radiation belt of a planet to capture its electrisity once every 24 hours, capturing it in a big and ridiculously effective ring of hardlight. From the surface, it looks like an aurora borialis is wrapped around a glimmering long and very large star in orbit. Those who tune their radios can hear a strange double pulse every 8 seconds and a sound like whale-song of the hardlight collector working, as if Null had a heartbeat.
The design should seem oddly familiar, like that Lorath sword I posted earlier.
Doesn't take a genius then, to work out who built this?