Cut Halo: The Master Chief Collection customization

Throughout its history, Halo: The Master Chief Collection has seen a huge variety of player customisation options. Many of these options have been removed from the game in subsequent updates, though several have never been useable.

Blackguard Tearful Bishop
"The faith of the newly converted burns bright enough to consume any truth."

The Tearful Bishop helmet was available as part of the flighting test for Season 8: Mythic, though was cut from the final release for unknown reasons. The helmet would have been available as part of the Blackguard series of Fracture armour for Halo 3 and Halo: Reach.

Belos Valorous
In the original flights for Season 8, the Valorous shoulder piece for the Belos Fracture set featured a large V symbol. In the final release, this was changed to the Season 8 lion emblem, for unknown reasons.

Blaster
One of many armour sets created for the now-cancelled Halo Online, the Blaster armour appeared in the game files for the Season 7: Elite flight, though has since seemingly been cancelled from implementation.

Extractor
Another cut Halo Online armour set intended to be included in Halo 3, this set's icons were included in the flight files for Season 7 though ultimately never released.

Knight
Another cut Halo Online armour set intended to be included in Halo 3, this set's icons were included in the flight files for Season 7 though ultimately never released.

Preserve
One of several pieces of equipment cut from the original release of the Anniversary Map Pack for Halo: Reach in 2011, the "Preserve" chest can be found in the files of the collection, fully-textured. Unlike its siblings in the EXO/TSCS chest and AKIS & Mariner helmets, this chest has yet to be implemented for use as an armor permutation.

Operator
Another cut Halo Online armour set intended to be included in Halo 3, this set's icons were included in the flight files for Season 7 though ultimately never released. This set can be seen in the Season 5 Trailer.

Spectrum
Another cut Halo Online armour set intended to be included in Halo 3, this set's icons were included in the flight files for Season 7 though ultimately never released. This set can be seen in the Season 5 Trailer.

Utility
Named "Utility" in the files, this Halo Online iteration of the DEFENDER-class Mjolnir was included in the flight files for Season 7, though was ultimately never released.

Rhine
Named the "Rhino" armor in the files, this Halo Online armor set was changed prior to its release as shown by its unused icon images, which display it having no gold, no forearms and different shoulders. This also could mean that Rhine was originally unlockable via the Season 6 Pass.

Skins
The following skins for Combat Evolved have been made unavailable for use.

Unreleased
Skins with the following filenames were shown as icons in the files of the collection for a time when Season 2: Spark launched, though have since been removed. All resembled pink placeholder textures.

Removed
Two skins for the Halo: Combat Evolved Warthogs, both referencing Jurassic Park, were later removed from the game in the Season 5: Anvil update for unknown reasons. The skins were replaced with the Park Ranger and Field Medic skins, respectively.

Nameplates
The following nameplates were changed or removed from The Master Chief Collection at various points, or were never available to use.