Each unit in Star Wars: Legion has a rank. When building an army, a player is restricted on the number of units of each rank they may include as follows:
Commander: Each army must include one to two commander units.-
Operative: Each army may include up to two operative units. -
Corps: Each army must include three to six corps units. 
Special Forces: Each army may include up to three special forces units.-
Support: Each army may include up to three support units. 
Heavy: Each army may include up to two heavy units.