Support upgrades are armor mods for the MJOLNIR [GEN2] armor that enhance a Spartan's combat performance in the field. They can be accessed through each loadout before a match is started or during a player's respawn time. While some support upgrades are available since the beginning of the game, others are unlocked via Specializations.
 List of upgrades
- Ammo: overrides the normal ammunition carrying capacity of the GEN2 armor, allowing a Spartan to exceed normal ammunition-carrying parameters.
- Awareness: adjusts MJOLNIR's heads-up display mechanics, allowing the integration of a motion sensor into scoped weapon smart-links. Thus, it provides a Spartan with basic motion sensor data while sighting an enemy.
- Dexterity: speeds up weapon reloads and weapon swapping.
- Drop Recon: feeds the user the time and location of ordnance deployments prior to drops.
- Explosives: alters grenade performance, increasing blast radius and decreasing grenade damage received by the user.
- Gunner: increases how long a mounted weapon can fire before overheating. It also increases the user's movement speed when a weapon is detached from its turret.
- Nemesis: marks the location of the hostile who last killed the user on the HUD. It is obviously impractical in real operations and is exclusive to War Games simulations. It does, however, increase tension for targeted participants.
- Ordnance Priority: offers more frequent ordnance drops to a Spartan. It is available only in modes in which personal ordnance is allowed.
- Sensor: increases the range and sensitivity of the motion sensor. It is utilized by stealth operatives and infiltration specialists to provide heightened intelligence of all nearby enemies.
- Stability: increases aiming stability when being fired upon. Overall it makes the user flinch less when under fire thus allowing a steady aim on target.
- Stealth: decreases user movement noise and visibility in enemy VISR systems like Promethean vision and also increases lethality in assassinations.
 List of appearances
- Halo 4 (First appearance)