As it does with Destiny 2, developer Bungie will be hoping Marathon becomes enough of a success to let it support it with new content in the years to come. To that end, the studio has shared what to expect from the game's first two seasons.
Season 1 lines up with the title's launch later this week, on 5th March 2026. Given the name Death Is the First Step, it runs until June and the first major addition it'll have is a fourth zone called Cryo Archive. This is an "end-game zone on the Marathon ship, where you’ll solve security puzzles, unseal frozen vaults, and come face-to-face with an entity even the UESC fears".
Later on in Season 1, a Ranked Mode unlocks that rewards exclusive items based on your position on the ladder. There will also be a C.A.R.R.I. event, a new gun, more implants, and balance changes during the season, as seen in the image below:

Season 2 then picks up in June and runs until August, and has been given the much shorter name of Nightfall.
Separately, in a PlayStation Blog post, it's confirmed all post-launch updates will be free: "Marathon’s seasonal updates will be available to everyone. No expansions or DLC required."
Bungie doesn't detail the second season of content quite as much, but teases that there's going to be a night version of the Night Marsh zone, a new Runner shell, and a new system called The Cradle included. The latter shall "give you more autonomy over your Runner shell’s statistical strengths and weaknesses".
When a new Season launches, Marathon will trigger some progression resets. The following are reset: everyone’s gear, contract progression, faction progression, and player level.





