Halo Infinite's retail version only contains an installer and acts as a DRM check--it doesn't include a playable game.
Players who get their Halo Infinite discs early still won't be able to play campaign. That's because the disc doesn't have a full playable game and instead is basically a physical key that proves ownership of the game. Halo Infinite's full campaign still has to be downloaded and even then it can't be accessed until 343i activates the switch on December 8.
The news was discovered by Digital Foundry's John Linneman, who criticized Microsoft's decision on Twitter.
"My biggest complaint regarding Halo Infinite really is that the disc doesn't contain a playable game. This'll be the first Halo game you can't really own as a standalone copy. This is not a good trend and I hope MS reconsiders things like this."
Although 50GB+ Blu-ray game discs coming with 500MB install files has become the new norm for the games industry (and has been for some time) it's still disappointing and will make Halo Infinite preservation very difficult. It's a live game, after all, and 343i is going all-in on its live service approach...eventually, of course. Halo Infinite is far from the huge, 10 year-spanning games-as-a-platform experience that Microsoft and 343i have envisioned.
Remember the Halo Infinite campaign will be a singleplayer-only experience until at least 2023 when co-op is added. That's a long time away.
If you want to play on launch day be sure to pre-load the game PC and/or Xbox.