Armored Response Coalition

The Armored Response Coalition (ARC) is a global military crisis-relief initiative formed by the combined efforts of the Allied Nations and Dr. Samuel Hayden to oppose the Hell invasion of Earth. The ARC appears in Doom Eternal.

History
The ARC was established by the Allied Nations in 2151 to succeed where modern militaries are ineffective against the Hell invasion. Dr. Samuel Hayden, who served as the ARC's Lead Director and oversaw all aspects of ARC weapon and tech development, provided the ARC with cutting-edge Argent-powered technology as he re-purposed Earth-based UAC facilities, which were unaffected by the invasion due to their remote locations and high levels of automated security, to mass produce weapons to the initiative.

Since its inception, the ARC began running operations from the Mobile Command Carrier, a seaborne command center designed for long-range strike operations, and was tasked in locating the source of the Hellgrowth infestation and shutting down the emergence of Hell portals and closing the gate between dimensions. Under Hayden's guidance, the ARC was committed in an aggressive research and development program in pursuit of new technologies to face the Hell threat head-on such as AEGIS AR4s, exosuits, TIYER M7 MK.III, tank-like machines, and ATLAS T3s, Heavy Frame battle-mechs. But in spite of the advanced technologies, the ARC and humanity was fighting a losing battle.

The ARC suffered the loss of Hayden after committing in a failed counterattack coordinated by Hayden in Operation Hellbreaker. Though ARC soldiers managed to retrieve Hayden's robotic torso and had him closely guarded and tended by a crew of scientists.