A Support Servitor and repair unit equipped with a Heavy Bolter and Servo Arms. They can be produced in the Stronghold.
Unlike Servitors, Support Servitors can't build structures they can only repair. They also fare pretty poorly for offensive attack. For this, their best function is as frontline repairs. They can repair damaged defences while holding off enemy attacks. The upgrade of a thunderfire cannon can help with long ranged defence against vehicles.