CIO-class Mjolnir

CIO-class Mjolnir (Counter Intelligence Operator) is a variant of the MJOLNIR Powered Assault Armor [GEN2] manufactured by Acheron Security.

Design details
The CIO helmet has a tricloptically fixed multi-spectral imaging array, also known as a transponder array. The neural interface bypasses in the CIO helmet allow the wearer to create custom synesthesis profiles to remap the suit sensors with their own senses. The suit also has a galvanized sensory suite that rivals nearly all other similar service packages.

The chest has a modular sensory suite, and a silhouette dampener for motion sensor circumvention.

Development history
After seeing the need for highly trained, heavily armored personnel to be deployed deep into enemy-controlled territory, Acheron Security developed and manufactured the CIO-class armor, with its main focus on espionage rather than lethality. The armor was tested at the Acheron Trauma Sim, and was designed to operate in the Martian territory of Acheron Fossae.

Usage
Though rarely seen, it is utilized by a handful of SPARTAN-IVs and Counter-Intelligence Operators for intel acquisition and strategic data conveyance deep within enemy territory, often those who endure tier-nine theaters.

Several CIO-armored Spartans were deployed to Terceira, where they captured and transmitted information crucial to the recovery of the colony from Insurrectionist forces.

CIO is also used during information denial missions, hunting down enemy scouts and preventing them from acquiring data of tactical or strategic importance.

Halo 4 - GEN2
CIO was first introduced into the Halo games as an armor set in Halo 4. The armor has three available skins; Web (WEB), Ruin (RUIN) and Rush (RUSH).

Halo 5: Guardians - GEN2
The CIO set returns in Halo 5: Guardians. The helmet and body armor are unlockable as armor permutations through the Requisition system. The body armor includes the Aviator chest and shoulders, Ricochet forearms, and Recruit legs. The CIO set has no alternate skins.

Production notes
Promotional images for the "Ruin" skin also included the pattern on the Inner-plated wrist armor and Over-locking leg armor. The final release version of the "Ruin" skin only added the skin on the CIO's helmet, chest, and shoulder armor, leaving out the wrists and legs.

List of appearances

 * Halo 4
 * Infinity Briefing Packet
 * Halo 5: Guardians