Series 6: Raven

Season 6 is to be a season for Halo: The Master Chief Collection, anticipated to release some time in 2021. As of November 2020, work had begun on Season 6 content. Flighting for the season begun on February 26, 2021.

Season content
Season 6 is expected to add some or all of the following content into The Master Chief Collection;

Halo: The Master Chief Collection

 * Custom Game Browser: a new way to play with each other in MCC
 * FOV slider support for all Xbox One consoles
 * FOV slider will no longer be locked when Xbox Series X|S devices are set to 120hz
 * Double Keybindings
 * Mouse & Keyboard support for consoles
 * Advanced Audio options
 * View Model Customization options
 * Seasonal currency “store”
 * New nameplates

Halo 3

 * One new map for Halo 3 from Halo Online; Waterfall
 * Three new techsuit customization for Halo 3:
 * GEN2 Azure
 * GEN2 Gunmetal
 * GEN2 Maroon
 * The Halo 3 original Spartan model is now available when the player has the toggle option for Halo 3 skins turned off.
 * Three new Halo 3 visor colors:
 * Another Sunrise
 * Cool Depths
 * Neon
 * Back accessory customization for Halo 3:
 * Tactical Pack
 * Ammo Pack
 * Demolitions Pack
 * Communications Pack
 * Pulaski
 * Sword and Board
 * Six new armor permutations for Halo 3, originally from Halo Online:
 * COS-class Mjolnir
 * HAMMERHEAD-class Mjolnir
 * INFILTRATOR-class Mjolnir
 * LANCER-class Mjolnir
 * NOMDAGRO-class Mjolnir
 * RHINE-class Mjolnir


 * Four new ODST armor permutations for Halo 3, based on the ODST armors used by Fireteam Raven in Halo: Fireteam Raven:
 * ODST/COMM
 * ODST/DEMO
 * ODST/HVY
 * ODST/TAC
 * 9 new weapon skins and 13 new vehicle skins for Halo 3:
 * 2 for the BR55HB battle rifle
 * 2 for the SRS99D-S2 AM sniper rifle
 * 2 for the M90A shotgun
 * 1 for the M41 SPNKR
 * 2 for the MA5C assault rifle
 * 3 for the M12 Chaingun Warthog
 * 2 for the M12G1 Gauss Warthog
 * 2 for the M808C Scorpion
 * 4 for the M274 Mongoose
 * 2 for the AV-14 Hornet

Flights
Flighting for Season 6 was originally set to begin on or after February 18, 2021. The release was ultimately delayed, and Flighting began on the 26th. The Flight was designed to test Season 6 content in new features, though not all of it was available at the start. At the Flight's start, available content included;
 * Several new Halo 3 armor permutations.
 * Halo: Fireteam Raven armors.
 * RHINE-class Mjolnir from Halo Online.
 * Backpack accessories for Halo 3.
 * Two new multiplayer maps for Halo 3, originally from Halo Online.
 * Edge
 * Waterfall
 * Several new animated nameplates.
 * Several new Halo 3 skins.
 * In-game team switching

In an update later in the flight, the new season points store will be added alongside a number of bugfixes for the existing content. Due to player feedback, the map Edge has been delayed and will be released in a future season. Originally, this update for the flight was planned to add a custom games browser initally only supporting Halo: Reach, though this was halted due to time constraints.

Cut Season content
Season 6 was originally slated to release with two former-Halo Online maps. While Waterfall made it into the final release, the map Edge was cut from Season 6 during the season flighting, as 343 Industries felt the map needed "fundamental improvements" before release.