Maps for Halo: Combat Evolved and Halo 2, that were originally PC-exclusive, are set to be included in Halo: The Master Chief Collection.
This was confirmed by 343 in a post on Halo Waypoint, where they also answered a few questions regarding the use of radar in Halo CE matchmaking (there's some playlists where you can, others where it's disabled), custom game options ("all of the game types and custom game type options you remember from Halo: CE will be available in the custom games menu") and PC weapons ("you'll be able to select your weapon set in Halo: CE from a brand new list of weapon sets, including "classic," which will not include the Flamethrower or Fuel Rod Gun").
343 also released a couple of new screens from the new-look Halo: Combat Evolved, which you can see below.
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