Marathon Symbiosis lands Dec 8 with a free week

Marathon Symbiosis arrives December 8 with Expedition PvE, 3v3 Deathmatch, the Bishop shell and a free Open Play Week from December 8 to 15 for everyone.

FireGhost

November 10, 2026, 10:50 PM5 min read

Contents10 sections

Marathon Symbiosis launches on December 8. Bungie's Symbiosis press release reveals new PvE and PvP modes, a new Runner shell, two new weapons and an Open Play Week that lets everyone play for free.

Bungie released a new gameplay trailer on November 10. The extraction genre is busy right now, as ARC Raiders passing 17 million sales shows, and Marathon wants a bigger slice of that audience.

A firefight in a red-lit corridor in Marathon — A firefight in Marathon (Source: Bungie / Steam)

What comes with Marathon Symbiosis?

Bungie calls Symbiosis the first step in Marathon's evolution. The update is free for all players and adds new ways to explore, survive, compete and crew up on Tau Ceti IV. As a reminder, Marathon is a high-stakes FPS from the creators of Halo and Destiny, in which players scavenge loot on the lost colony of Tau Ceti IV.

Symbiosis content at a glance

Perimeter update: fungal growth, alien life, the underground Burrows and the submerged Reservoir
Expedition: a new PvE-only mode built around a three-run series, solo or with a crew
Deathmatch (Beta): 3v3 team deathmatch without risking your permanent loadout
Limbo: a social space with firing ranges and a dueling pit
Bishop: a fast, blade-wielding robot Runner shell
New weapons: the V17 Flamethrower and the Maverick revolver

Expedition stands out. There is no PvP threat, just new combat and environmental challenges, and Flash Boosts let you shape your build during each run. Deep under Perimeter, the Tick Queen is waiting.

What about the new weapons and Deathmatch?

Bungie labels Expedition as Phase 1, so the mode should grow over time. Deathmatch is an experimental PvP mode with short matches in which two crews fight for points without risking their permanent loadout. It is a low-pressure way to try weapons away from extraction stakes.

The new guns fill different roles. The V17 Flamethrower brings short-range area denial, while the Maverick adds a revolver with a hand-cannon feel. You can test both in Limbo's firing ranges or settle scores in its dueling pit. The Bishop shell is built around fast, surgical blade attacks.

An armed Runner inside a green-lit facility in Marathon — Inside a facility in Marathon (Source: Bungie / Steam)

How does Marathon Open Play Week work?

Open Play Week starts alongside Symbiosis and runs until December 15. Everyone can play during that window, including Expedition, the Bishop shell and the updated Perimeter map. Insider Gaming's report on Marathon's free week notes that Bungie did the same thing at the start of Season 2.

There is one important detail. If you buy Marathon after Open Play Week, you keep everything you unlocked. Players who crew up with Bungie, PS5, Xbox and Steam friends can also earn limited-time Crew Up rewards until December 22. Free trials are a common tool this season, as the Battlefield 6 Casino Heist update and free trial and the Payday 3 free weekend on Steam showed.

A Runner moving through a dark forest in Marathon — A forest scene from Marathon (Source: Bungie / Steam)

What does it mean for players?

Marathon launched on Steam on March 5, 2026, and is available on PS5, Xbox Series X|S and Steam with cross-play and cross-save. Console online play needs a paid subscription. It sells in Standard and Deluxe editions, and Insider Gaming puts the price at $40. The free week is a good chance to try it without paying.

Insider Gaming writes that the player base has not grown much lately, so Bungie is clearly using new modes and a free week to bring in new players. On the Sony side, where Bungie sits, the latest numbers look strong, as PS5 sales reaching 97.9 million shows. For more screenshots and video, Bungie's Symbiosis press kit is live.

Frequently asked questions

When does Marathon Symbiosis launch?

The Symbiosis update launches for all players on December 8. Open Play Week starts the same day.

Is Marathon going free to play?

Not permanently. During Open Play Week, from December 8 to 15, everyone can play for free. If you buy the game afterwards, you keep the items and progression you unlocked.