For Halo it was that it was Halo
For Halo 2 Dual Wielding,xbox live
For Halo 3 it was the Bubble shield,online 4 player coop,Forge, Armor Permutation and that it was the final Game
For Odst you could play as an Odst, Free roam, firefight and silenced weapons
For Wars it was a halo RTS
For Reach it was Jetpack and space combat with custom firefight
What was the big things for Halo 4 I know the return of Master Chief, Spartan ops and a new saga but wat in game do they have