Sorry, Halo 5 Is Not Being Added To The Master Chief Collection - GameSpot

Microsoft says again that it has no plans to bring Halo 5 to The Master Chief Collection.
The Master Chief Collection brings together four Halo games into one collection for the Xbox One.

Halo 2 (2004)

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Halo 3: ODST HD Was Never Planned - GameSpot

Was Halo supposed to end at 3?

Halo: Reach' Will Have 6.2 Million Multiplayer Maps On PC/Xbox Launch - GAMINGbible

Xbox One - Wikipedia

News - July, 2020

Halo: The Master Chief Collection' Rumoured to be Headed to PC - Bloody Disgusting

July, 2015

News - September, 2021

Halo: The Master Chief Collection' Smashes Two Million Copies Sold on Steam in Just Five Days - Bloody Disgusting

How Halo: The Master Chief Collection Rebounded To Become A Fan-Favorite Compilation - Game Informer

Why Halo 5 is NEVER Coming to Halo MCC!