Armoury is the complete list of Weapons, Armours and Vehicles and special items every player possess. The significance of MOBS is here. Every mob member can carry the best Armoury from each of these categories. Mercs and Bosses also are key factors. The more the number of mercs and Mobs more the armory you can carry to each fight. The maximum number is restricted as (5*Level ) for Mobs and (3*Level ) for Mercs.
What makes Mob Fights interesting is that, Bosses who join you as Mercs can carry a significant amount of Armory with them.