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PIONEER-class Mjolnir

From Halopedia, the Halo wiki

This article is about the MJOLNIR variant. For the UNSC Destroyer, see UNSC Pioneer.
GEN2 Front
Prototype Front
HTMCC H3 Pioneer Crop.png
Prototype Back
HTMCC H3 Pioneer Crop Back.png
Production overview


Acheron Security[1]

Testing site(s):

Acheron Trauma Sim[1]
ANVIL Station[2]




Recon in unknown environments


  • Passive, redundant environmental scanners
  • High-bandwidth storage capacity
  • Duel-locked YV-65 rebreather
  • Twin-plated visual sensor
  • PNR-S7 split-convex pauldrons
Used by security escort during the first exploration efforts on Installation 03.

PIONEER-class Mjolnir is a variant of the MJOLNIR Powered Assault Armor [GEN2] manufactured by Acheron Security.[3]



The PIONEER helmet features passive, redundant environmental scanners whose the sensor fidelity and high-bandwidth storage capacity make it ideal for detailed environment scans used in War Games and intelligence analysis scene reconstructions.[4] The helmet also has a duel-locked rebreather (YV-65) leveraged in hostile environments. It also features a twin-plated visual sensor for increased range of spectrum. The suit also has PNR-S7 split-convex pauldrons.[1]

Development history[edit]

As a result of the UEG's pioneer initiative in order to claim new territories for colonization, Acheron Security set aside a budget and design team specifically for such endeavors, and within months Pioneer was presented. The suit was eventually put into full production and tested at the Acheron Trauma Sim.[1]

It is intended primarily for reconnaissance operations in unknown or hostile environments,[5] and was constructed to endure the rigors of a potentially hostile, alien environment, and to optimize overall performance through inhibitor mitigation.[5] It also pairs advanced environmental sensors with Acheron's latest threat detection systems.[4] The early prototype of the suit[6] later recieved additional testing and upgrades at ANVIL Station following its initial usage on Installation 03.[2] The suit went into a full production run following its ANVIL testing.[6]


Pioneer-class armor is equipped by Spartans providing protection to ONI expeditionary groups.[5]

The armor's first, and most notable, usage was during the first highly-classified exploration efforts of Installation 03 by Ivanoff Station's research deployments.[1][3] Since then the Pioneer variant has been used in assisting in the security and protection of over two dozen field teams and science detachments.[1] Pioneer suits have also been used to protect science teams on colonies and even to protect planetary engineering rigs.[1]

In-game Information[edit]

Halo 3 MCC[edit]

In the Halo: The Master Chief Collection version of Halo 3, the Pioneer variant was added as part of Season 5: Anvil content. With the updated Halo 3 armor customization options, the players can now fit their Spartan with Pioneer helmet, chest, shoulders, forearms and legs. The description of the armor pieces are the same for every set.

Piece Description Unlock requirements (Halo 3) Unlock requirements (Halo: MCC)
HTMCC H3 Pioneer Helmet Icon.png
Acheron Security hopes that ANVIL testing will prove out improvements made after the suit's use on Installation 03. N/A (MCC-exclusive) Season 5 Tier 49, Season point 1
HTMCC H3 Pioneer Chest Icon.png
Season 5 Tier 34, Season point 1
HTMCC H3 Pioneer LShoulder Icon.pngHTMCC H3 Pioneer RShoulder Icon.png
Season 5 Tier 29, Season point 1
HTMCC H3 Pioneer Forearms Icon.png
Season 5 Tier 16, Season point 1
HTMCC H3 Pioneer Legs Icon.png
Season 5 Tier 51, Season point 1

Halo 4[edit]

Pioneer was first introduced into the Halo games as an armor set and associated Specialization in Halo 4. The armor has one available skin; Adept (ADPT).

Armor Description Unlock requirements (Halo 4) Unlock requirements (Halo: MCC)
H4 MJOLNIR Pioneer.png
Description (H4): Used by security escort during the first exploration efforts on Installation 03. Pioneer specialization rank 4 Unlocked by default.
Helmet description (MCC): Used by security escorts during the exploration of Installation 03.
Shoulders description (MCC): Modular left/right spaulder from Pioneer-class armor.
Chest description (MCC): Pioneer suits were the first testbed for inhibitor mitigation processors.
Pioneer Adept (ADPT) skin
Description (H4): Customized with ADEPT armor skin. Pioneer specialization rank 9 Unlocked by default.
Helmet description (MCC) Pioneer helmet customized with ADEPT coating.
Shoulder description (MCC) Pioneer left/ right spaulder customized with ADEPT coating.
Chest description (MCC) Pioneer chassis customized with ADEPT coating.

Halo 5: Guardians[edit]

Unlock: Uncommon REQ card

  • Helmet description: The sensor fidelity and high-bandwidth storage capacity in the PIONEER helmet makes it ideal for detailed environment scans used in War Games and intelligence analysis scene reconstructions.
  • Body description: The PIONEER is a reconnaissance and combat expedition Mjolnir variant, pairing advanced environmental sensors with Acheron's latest threat detection systems.

In Halo 5: Guardians due to the "Body" having a predefined customisation this armor set permanently has the following parts from Halo 4:

  • Body: Pioneer
  • Shoulders: Pioneer
  • Forearms: Contoured
  • Legs: Contoured


Normal gallery[edit]

Halo 4 skins[edit]

Halo 5: Guardians skin[edit]

List of appearances[edit]