Located closest to the core along the Steiner border. It is awash with military activity. So close to Terra distances are short, with most worlds no more than 1 or 2 jumps from a major garrison. There exists ample transportation capacity, with both mech and aerospace assets in high readiness. Rubigen contains several systems that were once part of the Commonwealth. The prefecture has been on the receiving end of Alessandro's campaigns, but he has made relatively little headway here.

ORESTES on the Steiner border is a former Lyran world, captured by the Combine many years ago. It bears the scars of war, but it is also both heavily populated (and strictly controlled), a major manufacturing center, and a key logistics waypoint. It is also one of the most heavily defended planets in the Combine.e

RUBIGEN is a small, dark and icy world in the heart of the prefecture. Formally it is the military headquarters of the local Tai-Sho, but in practice he directs operations from Orestes, which is located right on the front lines. Rubigen is also famous for its naval officers - abotu 15% of all Combine flag officers hail from this unassuming planet.

The worlds or NOX and THUN have been pointed out as potential targets for battalion-level raids, mostly because the Lyrans feel they have decent intelligence which rules out the presence of massive defending forces. The presence of smaller mech garrisons cannot be ruled out, however. Furthermore, rapid response by mobile reinforcements (aerospace interceptor elements included) is to be expected.

The world of SKANDIA deserves special mention: it is currently in a state of open rebellion against the Combine. Intel indicates the Skandians have amassed a small (battalion?) level mech force, and have hired a number of smaller merc companies as well. There is "at least" a full regiment of DCMS mech on site, hunting the rebels. Lyran intelligence fully expects the Combine to crush all opposition. According to reports the commanding officer is Takari's brother, Tai-Sa (Colonel) Kuma Tanida, although it may be he's subordinate to an unknown Sho-Sho (Brigadier).