Microsoft revealed that they will be shutting off the online services for Halo Xbox 360 games by January 2021. The company had a roadmap that it shared with fans, showing how the company plans to handle online services for some of its older titles. The roadmap dates back from Fall 2019, with the first phase being the one-time migration of over 6M pieces of Halo Xbox 360 Legacy UGC data to Halo: The Master Chief Collection.
The second phase of the roadmap was halting the digital sales for Halo games on the Xbox 360. The Halo games released on the 360 include Halo 3, Halo Wars, ODST, Reach, Combat Evolved Anniversary, Halo 4, and Spartan Assault. DLC for those games would still be acquirable at no cost. It should also be noted that the four mainline titles of the Halo series (along with ODST and Reach) are part of The Master Chief Collection that can still be bought for the Xbox One and Xbox Series X/S.
Phase 3 of the roadmap was simply sending out a reminder of the impending shutdown of the online services for the Halo Xbox 360 titles. Though originally planned to happen sooner, Microsoft will shut down the online servers on January 13, 2022, as phase 4. The shutdown will only affect the online functionality and multiplayer for the games. Everything else in the games, like campaign, should continue to work as intended. However, the shutdown will apply to the backward-compatible versions of the games as well.
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