I can tell you that none of the campaigns are going to ppay as they originally did. Which ie a dang shame. MixMaker117, myself, and two others discovered new invisible walls in Halo3 on Saturday. Where we could jump out of the maps, or glitch up to certain areas, we can't now. It takes a lot of the fun and charm out of the game's campaign. I don't have Halo 1 nor 2 so I canr comment on them.

I don't understand why 343i (or Bungie) added these new barriers to the campaign missions. It wasn't hurting anything by allowing fans to leave maps they've played dozens of times. Allowing us to do these silly things added gameplay, unigue gameplay at that. It keeps it fun and entertaining. Now we have to "stay on point" the entire time. Killing marines now make it impossible to enter dropships. Even after they've "forgiven" your mindless rampage against them.

PS: Sprint better return for Halo5's campaign.
And if MP maps get bigger then it'll be needed in it as well.