Redditor WickedSoldier991 discovered the modes are visible when you play Halo Infinite offline and pointed out that you can save them to your file share to then access them online. The really interesting thing here is that these aren’t just variants of the same modes already available in matchmaking. There’s one entirely new game format called Attrition, where each team has a limited pool of respawns (like Battlefield’s ticketing system), and you win by draining them. There’s Elimination, an Attrition variant with no respawning played across multiple rounds a la Counter-Strike. And there’s Tactical Slayer, Infinite’s version of SWAT (no shields, no radar). 343 hasn’t talked about any of these modes or revealed them publicly, though their names have leaked.
There are 17 predefined multiplayer modes to choose from when starting a custom game in Halo Infinite. The majority of these can be found in online matchmaking: classics like team Oddball, 2-flag CTF, and a Slayer Big Team Battle variation. However, if you start Halo Infinite with Steam turned off, you’ll find 14 more modes designed by 343 Industries that aren’t ordinarily displayed.
Attrition sounds like a variant of Slayer, but it’s actually its own mode, including some cool options like kills granting your team additional respawns, and allowing you to revive allies. It also has a “Danger Zone” that encloses the map, Battle Royale-style.
These 14 hidden modes include several variants of the above, including the interesting Attrition Dodgeball, and a few Fiesta variants that haven’t been in matchmaking yet, including the surely chaotic Fiesta CTF.
In theory I love that I can create a CTF match and customize every detail—whether the flag returns instantly on touch, how many grenades we can hold, even how fast we can strafe—but starting from scratch means spending a lot of time in a lot of menus. It’s a lot easier to just run with one of the default modes created by the developers. And bizarrely, 343 doesn’t let you just choose the base mode from a simple drop-down box—the only way to create a mode of your own is to use an existing one as a base. As far as I can tell, you can only access Attrition by going offline and copying 343’s template (or grabbing it from someone else’s file share once it spreads).
You could roll your own Tactical Slayer configuration in custom games, but these presets created by 343 give us a pretty good hint at what to expect to show up in matchmaking over the coming months. And it’s just nice to have these modes to choose from instead of having to build your own, because Halo Infinite’s custom game setup is overwhelming.
If you want to save these modes to use yourself, set Steam to offline mode, boot up Halo Infinite, and open the custom game menu. Choose one of the modes, click Mode Editor, and then press ‘R’ to save a copy.
Here’s a full list of the modes you can only see offline.
Arena: Attrition Arena: Attrition Dodgeball
Arena: Elimination Fiesta: Attrition
Fiesta: CTF Fiesta: One Flag CTF
Ranked: One Flag Tactical: Slayer
Ranked: Elimination Fiesta: Strongholds