Society Military Structure

The Prime system is the main military structure used by Society cells. The smallest formation in the Prime system was the Un, which included 1-7 armored units (or three platoons of infantry). Three Uns formed a Trey, the smallest formation deployed independently, albeit very rarely. Two Treys working together under a command Un formed a Sept. The Society typically deployed one to two Septs on independent missions, while a single Sept or a group of up to four independent Treys were often assigned to augment corrupted Coyote forces. Corrupted Coyotes themselves did not use the Prime system, retaining the Clans' original system.[1]

Unit Formation Size Information
Un One BattleMech, three battle armor troopers, three conventional infantry platoons, three ProtoMechs, three aerospace fighters, seven combat vehicles The smallest Society formation, roughly equivalent to a Clan Point.
Trey Three Uns The smallest formation deployed independently, albeit rarely. Roughly equivalent to an under-strength Clan Star.
Sept Seven Uns (2 Treys + 1 Command Un) The largest formation formally recognized in the Prime system, roughly equivalent to an over-strength Clan Star or Binary depending on the unit type.


  • The Prime system is designed such that all BattleMech formations result in formation sizes that are prime numbers (1, 3, 7). Other unit types include prime numbers as part of their Un-level formation size. Despite appearing before 7 in a series of prime numbers starting from 1, no formations include 2 or 5 units (though this is likely to maintain parity with BattleMech formations, and to distinguish Prime from the Clan system which regularly uses quantities of 2 and 5).
  • Vehicle Septs were considered exceptionally rare. Vehicles were usually sorted into Treys, and deployed alongside other ground forces as part of a mixed Sept or group of Treys. As a result, vehicles have no entry on the Sept row of the Society Unit Definition Chart. Such a formation would have 49 vehicles.
  • Under the Prime system, the Society is one of three notable factions to field AeroSpace Fighters with a smallest-formation size other than 2. Society and Capellan Confederation armed forces both field their Flight-equivalents in groups of 3. The other exception is the Marian Hegemony.


  1. The Wars of Reaving Supplemental pp. 2-3