OSTEO combat engineering suit

The OSTEO combat engineering suit, also known as the HAZMAT armor, is a human armor system employed by unaugmented personnel as well as Spartan Operations personnel for HAZMAT operations. The suit was created as part of Project: OSTEO.

Design details
The OSTEO armor platform incorporates an array of contingency systems focused on surviving extended operations in extraordinarily harsh working and combat environments. It is designed to be used by both Spartans and non-augmented personnel in all manner of dangerous conditions. While the Spartans' MJOLNIR Powered Assault Armor already protects against many things, the OSTEO is more specialized towards the specific role of protecting against natural and artificial environmental hazards, and provides a platform that is not exclusively usable by Spartans. Where MJOLNIR offer protections to a Spartan operating in compromised conditions, OSTEO-derived technologies maximize life maintenance effectiveness for extended periods, providing more optimized solutions for a wider range of suitable operators—including non-augmented military and civilian personnel.

The OSTEO armor platform—even when utilized by civilians—is outfitted with onboard solutions to interface with various infotech and artificial intelligence control systems, which have become ubiquitously integrated into twenty-sixth century industrial and environmental infrastructures. These features give OSTEO wearers the agility to deal with both the technological and physical sides of hazardous events that might befall a human colony or installation.

Development history
In the years after the Human-Covenant War, private industry across several human colonies saw rapid development in many fields, with exoskeletal frames seeing considerable research and development. Project: OSTEO and its resulting combat engineering suit were among the fruits of these advancements. Primarily developed by Imbrium Machine Complex, the OSTEO armor system is the result of a shared-source initiative to build an armor platform wearable by both supersoldiers and non-augmented humans for everything from construction and exploration to security and combat applications. In the wake of the galaxy’s most recent conflicts, the United Nations Space Command has expressed interest in projects like OSTEO, modifying industrial-focused designs to used by Spartans and special forces operatives.

Usage
OSTEO armor is used by personnel who are sent on missions deep into dying Forerunner facilities, for hunters operating in and around poisoned water and air, search teams exploring sites scarred by chemical, biological, radiological, and nuclear weapons used in the Human-Covenant War, as well as those facing pockets of Flood infestation. It is also used by Spartan combat engineers working in demolition and hazmat missions, in addition to carrying out specialist tasks which require super-human reactions, strength, and situational awareness.

Variants
A list of variants compatible with the OSTEO armor platform:
 * Burrowlens
 * Mark VI CBRN
 * Notus
 * Oberon
 * Project CORSAC
 * Skarbnik
 * Steelheart
 * Voidspear

Halo Infinite
Like Chimera before it, the Hazmat armor core was available by default during Season 04: Infection, the fourth season of Halo Infinite multiplayer. It was first revealed on May 26, 2023, in an advertisement for a cross-promotion with Dr. Squatch soap.

Trivia
The OSTEO combat engineering suit is likely named after the Greek word ostéon, meaning "bone."

List of appearances

 * Halo Infinite
 * Season 04: Infection