Season 00: For Our Tomorrow
From Halopedia, the Halo wiki
For Our Tomorrow will be the first multiplayer season of Halo Infinite multiplayer. As well as serving as the game's launch season prior to the debut of Season 01: Heroes of Reach, the season was demoed as part of the Halo Infinite Multiplayer Tech Preview.
Note: The following sections are based on information from the Halo Infinite Multiplayer Tech Preview, and may be subject to change upon final release.