Halo 2 Anniversary is a 2014 first-person shooter video game developed by 343 Industries, Saber Interactive and Certain Affinity, and published by Microsoft Studios, It is a remaster of the 2004 game Halo 2, originally developed by Bungie for the Xbox. The game was announced at Microsoft's conference during the Electronic Entertainment Expo 2014 in June, and originally released on November 11, 2014 for the Xbox One to commemorate the game's tenth anniversary. It was included as an installment of Halo: The Master Chief Collection, a compilation comprising it alongside the other four numbered Halo entries released at that time. Anniversary would be released for Windows as part of The Master Chief Collection in May 2020, and for Xbox Series X/S in November 2020.
Following the release of Halo: Combat Evolved Anniversary in 2011, series developer 343 Industries intended to develop a similar remaster for the game's sequel to coincide with the Xbox One's launch. As with Combat Evolved Anniversary, the studio contracted Saber Interactive and Certain Affinity to respectively rework the game's campaign and multiplayer assets for the console's improved hardware. The game received a substantial visual overhaul in tandem with updates to the soundtrack and in-game audio as well. Blur Studio was commissioned to remake the cinematics for the campaign, as well as create two new cutscenes that would narratively connect Halo 2 to the storyline in the then-upcoming Halo 5: Guardians (2015).
At release, Halo 2 Anniversary received mostly positive reception, with praise primarily directed at the remade campaign, including the enhanced graphics, audio and the redone cutscenes. As with the rest of The Master Chief Collection at release, the multiplayer garnered mixed reactions for its problematic matchmaking, numerous bugs and inconsistent performance. The game would receive numerous post-release patches to address these issues, leading to a retrospective appraisal of the remaster in due time.