WAR MASTER-class Mjolnir

The MJOLNIR Powered Assault Armor/War Master is a variant of the MJOLNIR Powered Assault Armor [GEN2] utilized by SPARTAN-IVs.

Development history
The MJOLNIR/War Master variant is manufactured by Lethbridge Industrial. It is Lethbridge Industrial's most popular and most exotic armor system. It was tested at Lethbridge, Corsica on Concord. War Master-class armor is a multi-use, multi-functional configuration, which, when utilized properly, can benefit the user in almost any combat scenario propagated on the battlefield.

Halo 4
Unlock: Achieve Spartan Rank 37 Available skins: PRML(Primal)
 * Description: Lethbridge Industrial's most popular armor set is ironically its most exotic.
 * The PRML skin is obtainable by completing the King of the Hill Victory - Master commendation.

Behind the scenes
Based on its skull-like appearance, the War Master helmet seems to be a canonical counterpart to the Haunted helmet from Halo: Reach.

List of appearances

 * Halo 4
 * Halo: Escalation
 * Halo: Spartan Strike
 * Halo 5: Guardians
 * Halo Online