They let us pick
The first (and hopefully only) Halo campaign that's simply no fun to play on your lonesome. Here's hoping Infinite is a better single-player experience.
The game that put Xbox Live on the map. Despite its historic multiplayer, lacklustre Arbiter missions let the campaign down in places.
343's first Halo game packs in a well paced campaign and some awesome new weapons. Shame the team nixed the Convenant's original sound effects.
Even though it doesn't let you play as a Spartan, this spin-off solidifies a decent place on this list as a jazzy, essential part of the Halo legacy.
One of the most influential shooters of all time. Thanks to the HD Anniversary edition, the original Halo's campaign remains a treat to play.
The best multiplayer game ever. Forget Mario Kart or Timesplitters 2; Halo 3's multiplayer is incredible. The campaign ain't half bad, either.
Bungie's farewell to its universe serves up comfortably the best campaign in the series. Brilliantly paced, Spartan shootouts don't get any sweeter.