Fans un-canceled Halo Infinite's split-screen with a menu-timing exploit

In September 2022 the Halo Infinite team walked back a years-old pledge to support split-screen co-op for the campaign, after repeated delays, dashing the hopes of anyone who wanted to play the story with a friend on one screen. Within days, players reported that split-screen worked on retail Xbox builds via a glitch — and analysts at Digital Foundry confirmed it after hours of campaign testing.

The recipe: sign each controller into its own gamertag (avoiding a reported bug that corrupts saves when two pads share a profile), start a campaign session, and at the instant the countdown hits zero, open the friends list and join a friend's online session. Then leave the fireteam, back out to Custom Game, switch the Server option from Xbox Live to 'Local Online', and press start on the second controller. A lobby that looks like a versus match becomes split-screen campaign co-op.

It behaved like a shipped feature rather than a broken one: achievements doled out properly to all signed-in players, up to four players ran on one console, Digital Foundry measured locked 60fps on Xbox Series X and solid frame rates even on Xbox One at a blurry 540p, and the grappling hook could latch onto teammates. Known bugs were cosmetic — flickering distant textures and mismatched time-of-day lighting after a cut scene.

The campaign co-op code was fully shipped, just disabled: joining an online fireteam at countdown zero re-enabled it, and a 'Local Online' server kept it on one console.

The feature was cut from the roadmap, not from the build — the co-op code path shipped intact behind a menu gate.

The online-join flow set the campaign state that local play needed, and nothing in the retail build blocked reusing it offline.

Players held a years-old public promise, which was motivation enough to audit menu timing frame by frame once the feature was canceled.

Canceled rarely means deleted. State machines keep their paths: if a feature is only gated at the menu, the fastest audit is playing the UI against its own timing.

As of the September 15, 2022 report the exploit was unpatched on retail consoles, while official networked co-op remained limited to the Halo Insider preview build. Ars Technica argued Microsoft could legitimize the working mode through the Insider sandbox rather than patch it away.