Halo 4 Armour
Recruit: Starting Armor
Warrior: Reach the Rank of SR-8
Air Assult: Reach the Rank of SR-11
Soldier: Reach the Rank of SR-15
Aviator: Reach the Rank of SR-17
Defender: Reach the Rank of SR-21
Recon: Reach the Rank of SR-26
E.V.A. : Reach the Rank of SR-27
Warmaster: Reach the Rank of SR-37
Scout: Reach the Rank of SR-38
Orbital: Reach the Rank of SR-41
Infiltrator: Reach the Rank of SR-42
Hazop: Reach the Rank of SR-43
E.O.D. : Reach the Rank of SR-45
Oceanic: Reach the Rank of SR-47
Enforcer: Reach the Rank of SR-50
Mk. VI: Complete the campaign on Legendary (Solo or Co-op)
C.I.O: Spartan Slayer Master
Gungnir: Slayer Victory Master
Venator: Assassin Master
Commando: Dominion Victory Master
Ranger: Combat Opportunity Master
Protector: UNSC Loadout Master
Vanguard: Forerunner Enemy Mastery
Raider: Halo Waypoint Classified Unlock
Fotus: Limited Edition Halo Xbox
Scanner: War Games Map Pass or Limited Edition Halo 4
Strider: War Games Map Pass or Limited Edition Halo 4
Deadeye: Pre-order from BestBuy / Play.com
Locus: Pre-order from Future Shop / Mighty Ape or Play Mountain Dew King of the Hill iPhone app
Operator: Unlocked After Completing Specialization
Wetworker: Unlocked After Completing Specialization
Pioneer: Unlocked After Completing Specialization
Pathfinder: Unlocked After Completing Specialization
Rogue: Unlocked After Completing Specialization
Tracker: Unlocked After Completing Specialization
Stalker: Unlocked After Completing Specialization
Engineer: Unlocked After Completing Specialization