Unidentified powered exoskeleton
From Halopedia, the Halo wiki
In July 2511, during the earliest planning phases of what would become Project: MJOLNIR, Halsey referred to the design of this exoskeleton, among others such as the Mark I prototype exoskeleton, for reference and inspiration. She sketched the prototype exoskeleton in her personal journal, with an annotation pondering how much of the design would remain useful for her upcoming power armour developments. However, she ultimately chose to start completely from scratch.
This exoskeleton design was later revisited years later by Project: HRUNTING and Project: YGGDRASIL,[Note 1] which jointly created the HRUNTING/YGGDRASIL Mark I ADS, an armour system which in most respects is visually identical to the exoskeleton, but reaped the benefits of years of additional experience and technological improvements, including advancements pioneered by Project: MJOLNIR.
Some sources, such as a Halo Waypoint video series, conflate this exoskeleton with early iterations of the MJOLNIR Powered Assault Armor. However, the armour is known to predate Project: MJOLNIR, thus this is a mistake.
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