While certain famous Regiments or Clusters are armed predominantly with one weight-class or even type of mech, these are the exceptions. The vast majority of units TO&E are culled from the Medium and Heavy weight-classes, with the Heavy weight-class in particular forming the backbone of most regiments and clusters. The Medium weight-class once the workhorse, is now more and more encroaching on the specialty and recon roles of the light weight-class.
The 50% Rule
All Mechs and vehicles, except those who are equipped with four (4) or more tons of cargo capacity, are classified Non-Infantry Combat Units (NICU). To better simulate the variety of forces deployed in battle a single army composition rule is in effect for Non-Infantry Combat Units (NICU).
RULE: At least 50% of the total number of NICU in a given force must be from the medium and/or heavy weight classes.
EXAMPLE: Player A has a force of 4 Mechs, 3 vehicles and 3 Battle Armor. This force has a total of 7 units classified as NICU. Of the 4 Mechs and 3 Vehicles at least 4 must be from the medium and heavy weight classes.a theatre of war.