Early adopters of Halo: The Master Chief Collection will get an updated version of Halo 3: ODST's campaign and a reimagined version of the Halo 2 multiplayer map Relic for free, developer 343 Industries has announced.

343 Industries says that development on the campaign for Halo 3: ODST has just begun. It will be available within Halo: The Master Chief Collection, upgraded to 1080p resolution, running at 60fps. If you played Halo: The Master Chief Collection between launch (November 11) and December 19, you'll get it for free.

The same is true for the Relic Halo 2: Anniversary Multiplayer Map, which 343 Industries will reimagine and remaster at 1080p and 60fps. 343 Industries said it chose this map based on its suitability for Slayer and Objective modes and its ability to support teams of varying sizes.

If you bought the game between those dates, you'll also get one free month of Xbox Live Gold, and an exclusive in-game Nameplate and Avatar. Find more details here.

Head of 343 Industries Bonnie Ross explained that the developer is offering these items for free in gratitude to fans that stuck with Halo: The Master Chief Collection during its troubled launch, which suffered from severe matchmaking issues.

"This has been a humbling experience and highlighted how we as a studio can – and need – to do better for Xbox fans around the world," Ross said. "We are so grateful to our fans who have stood by our side and we appreciate all of your patience as we worked through these issues."

Ross also said that a content update next week will add all 10 episodes of the cooperative experience Spartan Ops for Halo 4 to playlists, as well as address other issues.

For more on The Master Chief Collection, check out GameSpot's review and previous coverage.