Editing MJOLNIR Powered Assault Armor/Mark IV

{{Status|Canon}}
{{Pageimage|TFoRAS MarkIV.jpg}}
{{Armor infobox
|image=[[File:Douglas-042.png|125px]][[File:H5G - PK - Cartographer's Gift - Mark IV GEN1 render - 04.png|125px]]
|caption=Mark IV on the GEN1 (left) and GEN2 (right) platforms.
|manufacturer=[[Materials Group]]
|testsite=[[Damascus Testing Facility]]
|type=[[MJOLNIR Powered Assault Armor]]
|role=General combat
|weight=
|features=
}}
{{Quote|You're the only ones who can use them, Petty Officer. Who else could we give them to?|[[Catherine Halsey|Doctor Catherine Halsey]] to [[John-117]].{{Ref/Reuse|for115}}}}

Despite its name, '''MJOLNIR Powered Assault Armor Mark IV''' was the first production model of [[MJOLNIR Powered Assault Armor]]. The suit was issued to [[SPARTAN-II program|Spartan-II commandos]] on [[2525#November|November 27, 2525]],<ref name="First Issue">'''Halo: The Fall of Reach''', ''page 113'' ''page 136'' (2010 edition)</ref> and was in service until it was replaced by the [[MJOLNIR Powered Assault Armor/Mark V|Mark V]] on [[2551|November 24, 2551]].<ref>[http://halo.bungie.net/News/content.aspx?type=topnews&link=BWU_012910 '''Bungie.net''': ''Bungie Weekly Update: 01.29.10'']</ref>{{Ref/Note|''Halo: The Fall of Reach'' states that the Mark V was issued on August 29, 2552. However, the January 29, 2010 Bungie Weekly Update and Dr. Halsey's personal journal retcon this, stating that the Mark V was issued on November 24, 2551. In this context, the test performed by John-117 was intended to gauge the pairing of the Mark V suit with a piggy-backed AI rather than to observe the suit's performance ''per se'', as presented in the novel. ''Halo Waypoint''{{'}}s ''MJOLNIR Project 2'' video, released in 2011, erroneously presents the date given in the novel as valid.}} A hybrid variant could still be requisitioned by Spartan personnel as late as [[2558|October 2558]], albeit upgraded to function with the [[MJOLNIR Powered Assault Armor (GEN2)|MJOLNIR [GEN2]]] suite; such suits are notably still used by select Spartan-IIs.{{Ref/Game|Id=H5G|H5G|Armor customization (Halo 5: Guardians)|Mark IV GEN1 Body armor description|Quote=As the basis for the GEN1 Mjolnir standard, many components of the original Mark IV can be used with GEN2 techsuits and VISRs after firmware updates. This hybrid GEN2/MARK IV [GEN1] suit is still used by select Spartan-II's.}} With the advent of the [[MJOLNIR Powered Assault Armor (GEN3)|MJOLNIR [GEN3]]] in [[2559]], the Mark IV was upgraded to be fully compatible with the new platform, and it can be requisitioned by Spartan personnel as late as [[2560]].{{Ref/Game|Id=HI|HINF|Armor customization (Halo Infinite)|Armor Hall|Detail=Mark IV - Helmet Description|Quote=The Halsey-refit Mark IV helmets are masterpieces of military engineering. Each is a refurbished Covenant War-era relic, stripped down and packed with the latest Mjolnir technology.}}{{Ref/Game|Id=HIAHCoreMarkIV|HINF|Armor customization (Halo Infinite)|Armor Hall|Detail=Mark IV - Armor Core Description|Quote=Stocks of Mark IV armor recovered from the Damascus archives have now been rebuilt under the direction of Dr. Halsey. These refits are fully compatible with official GEN2 and GEN3 standards but Halsey has her own ideas about the next step for Mjolnir.}}

==Introduction==
[[File:HM-MarkIV.jpg|200px|thumb|left|Diagram of the Mjolnir Mark IV.]]
Developed parallel to the SPARTAN-II program<ref name="Sybex">'''Sybex [[Halo: Combat Evolved (PC port)]] Strategy Guide''', ''page 5''</ref> by the [[Office of Naval Intelligence]]'s [[Materials Group]], the MJOLNIR powered assault armor was a radical redesign from previous large, bulky exoskeletons, streamlining their design into a compact suit of armor practical for use in the field. The brainchild of Dr. Catherine Halsey, the MJOLNIR armor represented her vision of creating a slim powered exoskeleton capable of taking full advantage of the physical capabilities of a SPARTAN-II.{{Ref/Reuse|Sybex}} Planning and research for the revised MJOLNIR battlesuit began in 2511{{Ref/Book|Id=halsey1|Dr. Halsey's personal journal|Detail=July 30th, 2511}} alongside the SPARTAN-II project; over the course of 14 years, its development gave birth to many new technologies that would later see major adoption throughout the military. 

MJOLNIR is a sealed system capable of [[extra-vehicular activity]] or operations in toxic atmosphere and vacuum. It is hardened against [[electromagnetic pulse]] and radiation, and has filters that are completely effective at removing toxins and bacteria from local atmosphere.<ref name="xbox">'''[http://www.xbox.com/en-US/games/h/halo/spotlight2.htm Master Chief's Armor: An Overview]'''</ref><ref name="FoR120">'''Halo: The Fall of Reach''' ''page 120'' ''page 143'' (2010 edition)</ref>

The armor's outer shell is composed of a multilayer alloy of remarkable strength which has been augmented with a refractive coating capable of dispersing a limited amount of Covenant [[Directed energy weapon|energy weapon]] impact.{{Ref/Reuse|xbox}}<ref name="FoR">'''Halo: The Fall of Reach''' ''page 114-115'' ''page 137'' (2010 edition)</ref> Underneath the alloy shell is a thick black armored titanium nanocomposite bodysuit. Underneath that layer is a gel-filled layer. The gel layer regulates temperature and can reactively change its density in a few seconds.{{Ref/Reuse|xbox}}{{Ref/Reuse|FoR}} The inner skinsuit is made of a moisture-absorbing synthetic material linked to an environmental control computer and the occupant's [[Spartan neural interface|special-issue neural interface]].{{Ref/Reuse|xbox}}{{Ref/Reuse|FoR}} This network translates electrochemical signals to digital code and routes them through an interface connection at the rear of the skull.{{Ref/Reuse|xbox}} Through this interface the user's thoughts commands the armor's movement and weapons and input from the on-board sensors comes directly to the user's mind.{{Ref/Reuse|xbox}} The synthesis of machine and mind is so fast that it is almost impossible to chart the reaction time. Unfortunately, the system is so reactive that normal human beings cannot use the suit without injuring or even killing themselves. Only humans who have undergone the skeletal, neural and muscular [[Biological augmentation|augmentation]] shared by the Spartans are able to safely operate the suit.<ref name="for115">'''Halo: The Fall of Reach''', ''page 115'' ''page 138'' (2010 edition)</ref>

Sandwiched between the external armor and the internal padding is the most devastating weapon the suit carries: a layer of [[polymerized lithium niobocene]], a form of reactive metal liquid crystal.{{Ref/Reuse|xbox}} Woven by molecular tools into a super-dense layer, this layer is amorphous, yet it amplifies force, doubling lifting capability and decreases reaction time by a factor of five.{{Ref/Reuse|Sybex}} Such technology did not exist when work began on the [[MJOLNIR Powered Assault Armor#Mark I exoskeleton|Mark I prototypes]].{{Ref/Reuse|Sybex}}<ref>'''Halo: The Fall of Reach''' ''page 70'' ''page 89'' (2010 edition)</ref>

Because of these advancements, the design is more akin to a conventional suit of armor as opposed to a powered exoskeleton; the user moves the suit and in return the suit moves the user. This allows for a highly compact design when compared to other combat systems. The armor contains numerous features including an integrated computer system which continuously monitors weapons and biological functions, as well as a limited function motion sensor system. The suit also contains a built-in rebreather system that can provide air for up to 90 minutes.{{Ref/Reuse|FoR120}} The suit's helmet also features imaging and video recording, and thermal sensors among other features.

In its final phase, a Spartan 2 wearing the armor weighs half a short ton (453.6 kilograms).{{Ref/Novel|Id=TFoRP|TFoR|Prologue}} At the time of its creation, it was the most advanced piece of tactical military hardware in human hands.{{Ref/Reuse|xbox}}

==Development==
[[File:Mark IV schematic.jpg|200px|thumb|A Mjolnir schematic dated September 25, 2524.{{Ref/Note|Although the in-universe filename of this diagram, ''MkIV-schem_092524-B109.tif'', identifies the armor as "MkIV", it is dated to more than decade before the Mark system was adopted.}}]]
The Mark IV underwent several generational design changes throughout the [[Human-Covenant War]], becoming a testbed for new technologies and hardware to help improve its integrity and efficiency in certain combat conditions.<ref name="mjolnir">'''[http://halo.xbox.com/en-us/intel/theuniverse/tech/video/the-mjolnir-project-1/cf313a1a-e1e5-4be8-a9a2-7071eda6ca8f Halo Waypoint: The MJOLNIR Project Part 1]'''</ref> While some of these variants are rumors and have never been witnessed in the field, others have become common knowledge.{{Ref/Book|Id=eync8889|Enc09|Page=88-89}} 14 variants had been developed by [[2535#January|January 7, 2535]].<ref name="journal">'''Dr. Halsey's Personal Journal''' ''January 7th, 2535 entry''</ref> The armor's external design went through multiple iterations;<ref>[http://halo.xbox.com/blogs/Headlines/post/2012/07/19/The-Halo-Bulletin-71812.aspx ''The Halo Bulletin: 7.18.12'']</ref> variants designed for a specific purpose tend, by necessity, to look different from the contemporary core model.{{Ref/Reuse|way-mjol}} However, each generational "Mark" is categorized by its internal components and software suite, not by its superficial appearance; therefore, while some Mark IV suits may look drastically different from one another, they are still essentially the same model.<ref name="way-mjol">'''[http://halo.xbox.com/en-us/intel/related/video/the-mjolnir-project-2/46e89c1a-f619-41e2-ad7f-ab65c61ca2df Halo Waypoint: The MJOLNIR Project Part 2]'''</ref>   

In February 2525, [[UNSC Special Forces#Naval Special Warfare Command|Naval Special Warfare]] received a prototypical suit for evaluation and final testing. Over the next four months, the unit was tested to ensure proper function and to evaluate its capabilities. However, the prototype was built and fine-tuned for the SPARTAN-II supersoldiers. When a test was conducted to see if a normal human could operate the suit, an override meant to prevent unintended use led to the operator being killed by his own muscular twitches.{{Ref/Reuse|for115}}{{Ref/Book|Id=hals2|Dr. Halsey's Personal Journal|Detail=June 30, 2525}} A short time after the failed demonstration limited production of the MJOLNIR battlesuit was approved.{{Ref/Reuse|hals2}}

MJOLNIR was first issued to the Spartan-IIs on [[2525#November|November 27, 2525]].<ref name="First Issue"/> Numerous variant models, including the skunkworks [[Project COBALT]],<ref name="HCDHBJ117"/> had been introduced by [[2526#April|April 2526]].{{Ref/Reuse|TAS}}{{Ref/Film|Id=FUD|H4FUD}}

By 2535, the MJOLNIR system had become the single most expensive item ever produced by the UNSC,{{Ref/Novel|Id=GoO2|GoO|Chapter=2}} with each suit costing as much as a [[UNSC destroyer|destroyer]] to manufacture.{{Ref/Film|Id=TSSF|HLeg|Story=Halo: The Story So Far}} Although the project had been intended as a continuous, pioneering effort to shatter technological barriers,<ref name="TSSF"/> on or shortly before January 7, the budgetary commission overseeing the MJOLNIR project mandated a simplified generational system to categorize, prioritize, and serialize development neatly into fiscal-year budgets. Thus the "Mark" system was introduced, with the systems developed thus far being retroactively designated "Mark IV" to suggest continuity with the powered exoskeleton program that had preceded MJOLNIR's development.{{Ref/Reuse|hals3}}

Shortly after the budgetary meeting, Dr. Halsey brainstormed numerous improvements for the project going forward (including a number of design sketches), ranging from the now-redesignated Mark IV through the then-hypothetical [[Mark VII]]. Her conception for the Mark IV included technologies not available at the beginning of the war, including a standardized vacuum survival system, standard fusion power, and a new radar sensory package.{{Ref/Book|Id=hals3|Dr. Halsey's personal journal|Detail=January 7, 2535}}

===Advanced Hardware Program===
The MJOLNIR Advanced Hardware Program concerns the development and furthering of hardware and technologies for testing, evaluation, and incorporation into later versions of the Mjolnir armor. The original goal of the program was to produce new technologies to aid the Spartan-IIs in the war against the Covenant,{{Ref/Reuse|eync8889}} such as the prototypical [[energy shielding]] tested as early as [[2531]].{{Ref/Book|EVG|Page=119|Quote=Energy shielding was a key feature of Mark V, although other Spartan squads had field-tested prototypes of this technology as early as 2531.}}<ref>[https://www.youtube.com/watch?v=E2geKWjvhPY YouTube: Halo Canon Exclusive Interview]</ref> Any changes in appearance of the armor are for research and development of future MJOLNIR components.{{Ref/Reuse|eync8889}}

==Suits==
The MJOLNIR Mark IV platform used several armor and helmet configurations during its service.{{Ref/Note|Many depictions of the Mark IV system currently lack official designations; such designs are presented here with physical descriptions.}}

===Base suit===
This suit was issued to the [[Spartan-II]]s during the [[Battle of Chi Ceti]] in November 2525.

====Variants====
[[File:TFoR AS - Baby Blue Team.jpg|thumb|250px|Various Mjolnir designs worn by [[Blue Team]] during the Battle of Chi Ceti.]]
*'''[[ÄRGER-class Mjolnir|MJOLNIR/Ä]]''' - Ärger - Testbed helmet created for testing design improvements for the Mark IV armor.
*'''[[ARDENT-class Mjolnir|MJOLNIR/Ardent]]''' - Ardent - A helmet that was upgraded by the [[Spirit of Fire]] crew during the [[Second Ark Conflict]].
*'''[[AIR ASSAULT-class Mjolnir|MJOLNIR/AA]]''' - Air Assault - Developed as an improvement of the ODST armor.{{Ref/Book|Id=EVG|EVG|Page=4}}
*'''[[CQC-class Mjolnir|MJOLNIR/CQC]]''' - CQC - Variant for close-quarters combat, including boarding actions and [[Wikipedia:Military Operations in Urban Terrain|MOUT]].{{Ref/Reuse|armor}}
*'''[[EMIL-class Mjolnir|MJOLNIR/E]]''' - Emil - Variant hardened to withstand an extended range of environmental conditions.
*'''[[EOD-class Mjolnir|MJOLNIR/EOD]]''' - EOD - Variant that improves the survivability of the user in close proximity to an explosion.{{Ref/Game|Id=armor|HR|The Armory}}
*'''[[GRENADIER-class Mjolnir|MJOLNIR/G]]''' - Grenadier - Intended to provide additional protection against concussive force. The helmet is an up-armored variant of a prototypical Mark IV design.{{Ref/Book|Id=EVGG|EVG|Page=85}} Used as a testbed for incorporating [[energy shielding]] technology into the MJOLNIR program.{{Ref/Reuse|armor}} 
*'''[[ISIDOR-class Mjolnir|MJOLNIR/I]]''' - Isidor - Variant crafted with the help of the prodigal Spartan-II combat engineers of Yellow Team.
*'''[[COMMANDO-class Mjolnir|MJOLNIR/K]]''' - Commando - Developed to improve a Spartan's tactical awareness on the battlefield.{{Ref/Book|EVG|Page=33}}
*'''[[SECURITY-class Mjolnir|MJOLNIR/M]]''' - Security - Variant designed for ship and military site defense.
*'''[[ÖKONOM-class Mjolnir|MJOLNIR/Ö]]''' - Ökonom - Variant created as part of ONI's failed Project: OPTIMUS.
*'''[[OPERATOR-class Mjolnir|MJOLNIR/Operator]]''' - Operator - Variant for ONI's Beta-5 Asymmetrical Action Group.
*'''[[PALADIN-class Mjolnir|MJOLNIR/Paladin]]''' - Paladin - One of Dr. Halsey's side projects, later improved with GEN3 Mjolnir technologies.
*'''[[PILOT-class Mjolnir|MJOLNIR/Pilot]]''' - Pilot - Variant developed for use by the [[UNSC Air Force]] that was adapted for compatibility with Mark IV.{{Ref/Book|EVG|Detail=Pilot page}}
*'''[[SCOUT-class Mjolnir|MJOLNIR/S]]''' - Scout - Variant uses advanced materials to provide stealth properties.
*'''[[THEODOR-class Mjolnir|MJOLNIR/T]]''' - Theodor - Variant made by [[Materials Group]] at the [[Special Warfare Center]].
*'''[[ULRICH-class Mjolnir|MJOLNIR/U]]''' - Ulrich - One of the first Mjolnir variants to feature programmable datacores dedicated to supporting modular equipment packages.
*'''[[VALIANT-class Mjolnir|MJOLNIR/Valiant]]''' - Valiant - Variant made by [[Emerson Tactical Systems]].
*'''[[WILHELM-class Mjolnir|MJOLNIR/W]]''' - Wilhelm - A classified variant made by [[Materials Group]] at the [[Damascus Materials Testing Facility]].
*'''[[YPSILON-class Mjolnir|MJOLNIR/Y]]''' - Ypsilon - Variant  fitted with a low-profile VISR prototype.
*'''[[ZACHARIAS-class Mjolnir|MJOLNIR/Z]]''' - Zacharias - Variant field tested by the first Headhunter deep strike teams.

===Project: COBALT===
[[Project COBALT|Project: COBALT]] introduced a new Mjolnir chassis for [[Blue Team]] early in the [[Human-Covenant War]].{{Ref/Comic|Id=HCDHBJ117|HCD|Detail=Hardcover bonus - John-117}}

<gallery>
File:HSS full cover.jpg|John-117 wearing his set of [[Project COBALT#COBALT CV.117|COBALT CV.117]] armor.
</gallery>

====Unidentified variants====
*'''Mark VI-like variant (2525)''': John-117 was equipped with this variant during the [[Battle of Chi Ceti]] on [[2525#November|November 27, 2525]].{{Ref/Note|The novel ''Halo: The Fall of Reach'' describes the Spartan-IIs as wearing identical armor during the Battle of Chi Ceti IV; the comics ''[[Halo: Fall of Reach - Covenant]]'' and ''[[Halo: Collateral Damage]]'' follow suit. However, ''[[Halo: The Fall of Reach - The Animated Series]]'' depicts the Spartans in distinct variants for the sake of the visual medium.}}
<gallery>
File:TFoR Animated - John Mark IV.png|John wearing the variant aboard the Covenant vessel ''[[Unrelenting]]''.
File:TFORAS_MarkIV_Helmet_Turnaround.jpg|Turnaround of the helmet.
File:TFORAS_MarkIV_Armor_Turnaround.jpg|Turnaround of the armor.
</gallery>

*'''Argus-like variant''': Linda-058 wore this helmet during the Battle of Chi Ceti. It is very similar in appearance to the Mark VI and GEN2 [[ARGUS-class_Mjolnir|Argus]] helmets she would later wear.
<gallery>
File:Mark IV Argus.png|Linda wearing the variant.
File:TFORAS_Argus_Helmet_Turnaround.jpg|Turnarounds of the Argus-like helmet.
</gallery>

*'''Centurion-like variant''': Fred-104 wore this helmet during the Battle of Chi Ceti. It is very similar in appearance to the Mark VI and GEN2 [[CENTURION-class_Mjolnir|Centurion]] helmets he would later wear.
<gallery>
File:Mark IV Centurion.png|Fred wearing the variant.
</gallery>

*'''CQB-like variant''': Though the [[CQB-class Mjolnir|CQB variant]] proper did not enter service until 2535, the helmet's physical architecture saw use as early as 2525.<ref>[https://www.halowaypoint.com/en-us/forums/db05ce78845f4120b062c50816008e5d/topics/about-that-fall-of-reach-animated-series-trailer/e114975f-ddcc-4109-bf72-e4d8efc29ec5/posts?page=2#post37 '''Halo Waypoint''': ''GrimBrotherOne'': Nothing has changed about the CQB variant of the Mjolnir armor system. Samuel is utilizing a developmental helmet permutation that shares visual cues with the eventual CQB. This kind of cross-germination of physical shape and design between all Mjolnir platforms was pervasive in the early development of Mjolnir at the Materials Group facilities.]</ref>
<gallery>
File:HTFORTAS Mark IV CQB-like Mjolnir.png|[[Samuel-034]] wearing a proto-CQB helmet at Chi Ceti IV in November 2525.
File:Homecoming_DaisyCQB_Concept.png|[[Daisy-023]] wearing a CQB-like helmet.
</gallery>

*'''[[EVA-class_Mjolnir|EVA-like variant]]''': A Spartan-II was issued this helmet during the Battle of Chi Ceti.
<gallery>
File:Mark IV helmet unknown fishbowl.png|A Spartan-II equipped with the helmet.
</gallery>

*'''Hermes-like variant''': Kelly-087 wore this helmet during the Battle of Chi Ceti. It is very similar in appearance to the GEN2 [[HERMES-class_Mjolnir|Hermes]] helmet she would later wear.
<gallery>
File:Mark_IV_Hermes.png|Kelly wearing the Hermes-esque helmet.
File:TFORAS_Hermes_Helmet_Turnaround.jpg|Turnaround of the Hermes-like helmet.
</gallery>

*'''Unspecified variant''': During the Battle of Chi Ceti, a Spartan-II tested out this helmet.
<gallery>
File:Mark IV helmet Prefect-like.png|A Spartan-II wearing the helmet.
</gallery>

===[[B-class Mjolnir|MJOLNIR/B]]===
Variants of Mark-IV [B] saw use as early April [[2526]].
====Variants====
*'''MJOLNIR/B armor worn by Fred-104''' - Personalized variant worn by [[Fred-104]] during the [[Battle of Circinius IV]] in [[2526]].{{Ref/Reuse|FUD}}
<gallery>
File:FUD-Fred-Helmet.jpg|The variant worn by Fred-104 in April 2526.
File:FUD-Fred-104.jpg|Footage of Fred-104 wearing this variant.
</gallery>

*'''MJOLNIR/B worn armor by Kelly-087''': During the Battle of Circinius IV in April 2526, [[Kelly-087]] utilized a helmet that had similar architecture to [[AIR ASSAULT-class Mjolnir]] with what looks to be an [[FJ/PARA attachments|FJ/PARA]] knee guard attachment affixed to the jaw. She wore the helmet in conjunction with a personalized set of [[B-class Mjolnir|Mark-IV [B] armor]].{{Ref/Reuse|FUD}}
<gallery>
File:FuD Kelly variant.png|The variant worn by Kelly-087 in April 2526.
File:H4FUD Kelly and John.png|Another look of the armor worn by Kelly-087 in April 2526.
</gallery>

====[[DEIMOS-class Mjolnir]]====
*'''DEIMOS-class Mjolnir (2526)''': John-117 was outfitted with this variant during at least four separate engagements during the [[Human-Covenant War]]. Considerably slimmer than Mjolnir's initial production model, this variant bears a strong resemblance to the later Mark VI, especially the Mark VI [[MJOLNIR Powered Assault Armor (GEN3)|GEN3]] suit he would eventually wear.
<gallery>
File:H4FUD-MasterChief-John117.png|John wearing the Deimos on [[Circinius IV]] in [[2526]].
File:H4FUD-MasterChief-MkIV-Views.png|John wearing DEIMOS-class Mjolnir.
File:Homecoming_John117_Concept.png|John's Deimos armor during the time of Daisy-023's death.
File:HaloLegends-MasterChief.png|John wearing the armor during [[Operation: WARM BLANKET]] in [[2544]].
File:CEV Meteorite MarkIV Helmet.png|John wearing a DEIMOS-class Helmet during [[Operation: METEORITE]] in [[2551]].
File:HBB_Owen.PNG|[[Owen-B096]] was likely outfitted with this Deimos variant during the first part of the [[Battle of Meridian]].
File:Merch-McFarlane-HLMasterChief front.jpg|Front view.
File:Merch-McFarlane-HLMasterChief left view.jpg|Left view.
File:Merch-McFarlane-HLMasterChief right view.jpg|Right view.
File:Merch-McFarlane-HLMasterChief back.jpg|Back view.
</gallery>

====Variants====
*'''Cohort-like variant (2544)''': [[Solomon-069]], [[Arthur-079]], and Fred-104 used this helmet during [[Operation: WARM BLANKET]]. It is very similar in appearance to the GEN3 [[COHORT-class Mjolnir|Cohort]] helmet Fred would later wear.
<gallery>
File:Mark IV helmet unknown.png|Solomon-069 wearing the helmet during Operation: WARM BLANKET.
File:Fred Combat Knives Halo Legends.jpg|Fred-104 wearing the same variant.
File:Merch-McFarlane-HLFrederic front.jpg|Front view.
File:Merch-McFarlane-HLFrederic left side.jpg|Left view.
File:Merch-McFarlane-HLFrederic right side.jpg|Right view.
File:Merch-McFarlane-HLFrederic back view.jpg|Back view.
</gallery>

*'''Hermes-like variant (2544)''': [[Kelly-087]] utilized this variant of armor during [[Operation: WARM BLANKET]]. Unlike the armor utilized by the rest of her teammates during the mission, this variant features heels and additional plating on the chest. It is very similar in appearance to the GEN3 [[HERMES-class Mjolnir]] armor Kelly would later wear.
<gallery>
File:Kelly-087 ThePackage.jpg|Kelly-087 utilizing this variant of armor.
File:Kelly-087 ThePackage 2.jpg|Another angle.
File:Kelly 3.jpg||Another angle.
</gallery>

===Unknown Mark IV suit===
*'''Gray Team variant''': In [[2535]], [[Jai-006]] wore a distinct variant of the Mark IV superficially resembling [[MJOLNIR Powered Assault Armor (GEN2)|GEN2]] [[RECRUIT-class Mjolnir]].{{Ref/Game|Id=Terminal1|H2A|H2A:Terminals|Terminal 1}}{{Ref/Note|The color of Jai-006's helmet visor during the [[Battle of the Rubble]] has been inconsistently depicted. Throughout ''[[Halo: The Cole Protocol]]'', Jai's visor is described as being gold. However, in ''[[Halo 2: Anniversary]]''{{'}}s [[H2A:Terminals|terminal]]s, his visor is depicted as silver.}} Another member of [[Gray Team]] wore a variant of Mark IV resembling [[MJOLNIR (B)|Mark V[B]]].<ref>''Halo: The Cole Protocol'' cover art</ref> 
<gallery>
File:CP armor.png|A member of Gray Team wearing the variant at [[the Rubble]].
File:Grey_Team_Mark_IV_variant.png|Jai-006 in his Mark IV variant.
</gallery>

===GEN2===
====Hybrid GEN2/MARK IV [GEN1]====
After the [[Human-Covenant War]], a [[MJOLNIR Powered Assault Armor (GEN2)|GEN2]] variant was developed that uses many components of the original Mark IV armor after firmware updates. This suit is still used as of [[2558#October|October 2558]],{{Ref/Reuse|H5G}} with [[Tom-B292]] using the armor's forearms.<ref name="GC">[https://www.halowaypoint.com/en-us/news/golden-clouds '''Halo Waypoint''': ''Community Update - Golden Clouds'']</ref>

<gallery>
File:H5G - PK - Cartographer's Gift - Mark IV GEN1 render - 03.png|The Mark IV adapted for MJOLNIR [GEN2].
</gallery>

====Red Team's hybrid GEN2/MARK IV====
After Douglas-042's Mjolnir Mark IV armor was damaged by [[Atriox]] in May