With the latest update for Halo: The Master Chief Collection, Microsoft and 343 Industries have improved the matchmaking component and other functions – also included was Halo 4’s unique Spartan Ops Mode.
The cooperative multiplayer mode featured an episodic mission structure and plot progression, and supported up to four players. Master Chief Collection’s enhanced version includes all 10 episodes from the original release and its ensuing DLC.
Additional fixes include tweaks to hit detection, improved roster updates, and Achievement/stat-tracking. Finally, players that disconnect from online matches before the end of the round will now receive a “loss.”
Source – Halo Waypoint