Marathon Symbiosis brings permanent PvE and a Deathmatch beta on December 8

Marathon is preparing a different kind of return to Tau Ceti IV. The Symbiosis update arrives on December 8, 2026, with dedicated PvE, a new competitive format and more room to explore. Bungie’s latest preview gives players a clearer picture of what they can try before deciding whether to come back.

Expedition and Deathmatch serve different players

Expedition introduces the first phase of Marathon’s permanent PvE experience. Its three-run structure supports solo play or a crew, with environmental and combat challenges instead of attacks from rival players. Flash Boosts let players adjust their build during a run.

Deathmatch takes the opposite route: short, experimental 3v3 matches focused on direct competition. Players compete for points without putting their permanent loadouts at risk. The beta label matters: this is a format Bungie is testing, not a finished competitive roadmap.

A familiar map gets new territory

Perimeter is being reshaped by fungal growth. The underground Burrows and submerged Reservoir expand its playable spaces, while the Tick Queen adds a new threat. Bishop joins the Runner lineup with a fast, melee-focused approach.

Between outings, the new Limbo social space gives players somewhere to meet and test equipment. The update also includes the V17 Flamethrower and Maverick revolver.

When can you try it?

Open Play Week runs from December 8 to 15. Players can try the game without buying it during that window; items and progress carry over if they purchase afterward.

Crew Up continues until December 22. Its Expedition challenges require playing with another participant rather than going solo. Access after the free week requires owning the game. Console players should also check their platform’s online-subscription requirements.

More options beyond extraction

Marathon’s existing extraction format combines scavenging with the risk of losing equipment. Symbiosis adds alternatives rather than presenting every session as the same high-pressure commitment. The open week gives players a practical chance to compare Expedition, direct PvP and extraction before committing to a purchase.