First Halo Infinite campaign co-op gameplay footage shows four Master Chiefs in action

gamesradar.com:

Developer 343 Industries streamed nearly an hour of gameplay of the long-awaited Halo Infinite campaign co-op beta, which is expected to kick off soon after getting a vague July 11-ish release date. 

The studio's campaign co-op flight preview stream starred community director Brian Jarrard, campaign lead designer John Mulkey, campaign lead engineer Isaac Bender, and program manager Ron Brown. All four appear in-game as Master Chief, as Halo Infinite campaign co-op doesn't use any generic Spartans in place of the hero himself. 

"We made the decision that we want to be able to play our campaigns together," Mulkey explained on the stream. "It's not like playing co-op is a different fictional construct. I'm playing my Master Chief story, you're playing yours, and we're getting to play together which is really, really fun. But when I go back to my solo campaign, it's my Master Chief story." 

The stream went about as you'd expect: playing the Halo Infinite campaign with friends looks fun. The devs showed off the co-op UI as they set up a session, adjusting difficulty and enabling Skull modifiers as they wish, and the mission sync works as described. Progress is shared, and if anyone in the party hasn't collected anything out in the world, it'll be available for them to grab and permanently unlock. 

Co-op lobbies also indicate how far each player has gotten in the campaign, which is part of 343's "No Spartan Left Behind" system. This basically means that any open-world activities or campaign missions which haven't been completed by everyone in the lobby will be playable in the co-op session, and clearing these with a group will also progress them in your solo game. This will let veteran players play with newcomers and, if they