It is actually very simple.
The game will come with a code like CEA which allows for you to activate a creative menu.
There will be two main menus for Halo 4
Classic Menu- This menu would have Campaign, Multiplayer, Firefight, and Theater.
Creative Menu- Forge 3.0, Custom Game Browser, and Theater
Basically the menu switching would work like going to Waypoint with Reach except the button too switch will be at the bottom of each main menu.
Now lets go step by step through this:
Campaign-with the new capabilites with games and the lack of forge and Custom Games 343 would be able to make the battles and sandbox better then any other Halo game. The campaign could be large and braud with amazing skyboxes all around!
Multiplayer- Well not much to say here it would work about the same as any other game. For the Ranking system 1-50 should return however there is a xp system within the rank system
Lets say you are trying to reach level 25 and just reached level 24 you need 6 points to go up
2points=win and MVP
0=win and MVP
Firefight- In firefight we should have a boss battle at the end of a wave so one map could be a couple of wraiths and another map could have a Scarab or Grave Mine as a boss!
Also I believe that an Invasion like firefight game should be added. You start off in a small section of the map and after every wave you unlock more of the map and better things like a Rockets, then a Warthog and so on until you have unlocked the whole map!
Theater-Not much needs to be changed except for allowing 4 player viewing and maybe a slow mo button…
Creative mode will be below this post.