Hello Infinite has now been found a new game mode: Last Spartan Standing.
The new mode is assigned to the Big Team Battle Playlist and designed for 24 players.
According to the description, there are no teams (free-for-all) and every soldier fights for themselves.
At Last Spartan Standing one seems to have served at the weapon game mode (Gun Game) from Call of Duty.
For the description of Levels players their loadout by achieving a personal score, and try to win the match as the last living spartan.
Whether the mode is actually playable in the Multiplayer by Halo Infinite will remain to be seen.