Bungie has revealed new details about Marathon’s upcoming Symbiosis update, launching December 8, 2026, for PlayStation 5, Xbox Series X|S and PC. The major update introduces Expedition, a new cooperative PvE mode featuring roguelite-style upgrades, alongside 3v3 Team Deathmatch, expanded map areas, a social hub, additional weapons and a new playable Runner shell. Players will also be able to try the game without purchasing it during an Open Play Week running from December 8 to December 15.
The developer showcased the upcoming content in a new gameplay trailer released on November 10, accompanied by announcements on the official PlayStation Blog and Bungie’s press website. Although Symbiosis was originally announced in September, the latest reveal provides the first detailed breakdown of its new gameplay modes, environments and equipment.
Expedition is one of the update’s most significant additions. Unlike Marathon’s traditional extraction gameplay, which combines encounters with hostile enemies and competing player-controlled Runners, Expedition focuses entirely on PvE. Players can enter alone or with a crew and complete a structured series of three runs without facing enemy players.
Each Expedition presents combat encounters and environmental challenges, with Flash Boosts allowing participants to modify their character builds during a run. These upgrades introduce roguelite progression elements, giving players opportunities to adapt their capabilities as they advance through the activity.
The December update introduces the first phase of Expedition rather than its complete planned evolution. Bungie previously described the mode as Marathon’s first permanent PvE experience, intended to provide an alternative to its existing PvPvE extraction structure.
Symbiosis also introduces Deathmatch, an experimental competitive mode launching in beta. The new activity features short 3v3 Team Deathmatch matches in which two crews compete to earn points.
Unlike Marathon’s traditional extraction encounters, Deathmatch allows players to fight without putting their permanent equipment loadouts at risk. This separates the competitive activity from the game’s usual emphasis on collecting valuable gear and surviving extraction.
The update substantially changes Perimeter, one of Marathon’s existing playable zones on Tau Ceti IV. Fungal growth and alien life have transformed parts of the environment, introducing two additional explorable areas called Burrows and Reservoir.
Burrows takes players underground, while Reservoir introduces submerged environments. The updated zone also features the Tick Queen, a new enemy lurking beneath the surface. Bungie has not yet detailed the encounter’s complete mechanics or rewards.
Another addition is Limbo, a dedicated social space where players can gather outside conventional extraction missions. The hub includes firing ranges for testing weapons and equipment, alongside a dueling pit where Runners can challenge one another.
Limbo gives players a separate environment for experimenting with their equipment and interacting with other players without entering a standard extraction match.
Bungie is also expanding the playable Runner lineup with Bishop, a new shell built around speed and blade-based combat. The developer describes Bishop as a fast, precision-focused robotic combatant, although its complete ability set has not yet been disclosed.
Two new weapons will arrive alongside Bishop. The V17 Flamethrower focuses on close-range area denial, allowing players to threaten nearby spaces with fire. The Maverick introduces a revolver weapon archetype designed around powerful handgun combat.
These additions provide further equipment choices across Marathon’s combat activities, although Bungie has not released detailed weapon statistics or balance information.
The update represents a significant change in Marathon’s ongoing development plans. In September, Bungie announced that content previously scheduled for an earlier update would instead arrive with Symbiosis on December 8. The studio also confirmed it was moving away from a rigid seasonal update schedule while developing additional gameplay improvements.
Symbiosis brings together several of those previously announced features, including permanent PvE content, a refreshed Perimeter zone, competitive Team Deathmatch and a social space. The November reveal establishes how these additions will function when the update becomes available.
Alongside the launch, Bungie will hold a free Open Play Week from December 8 through December 15. During this period, players who do not own Marathon can access the game and experience the new Symbiosis content, including Expedition, Bishop, the updated Perimeter zone and additional equipment.
Progression and items earned during Open Play Week will carry over for players who subsequently purchase the game.
A separate limited-time Crew Up event will run from December 8 through December 22. Players who team up with friends and complete cooperative Expedition challenges can unlock cosmetic rewards, including an emblem, player background, weapon sticker, weapon charm, Destroyer skin and title.
Crew Up challenges require players to participate with at least one friend who has joined the event, rather than completing the objectives entirely solo. The event continues for an additional week after Open Play Week ends, although players will need to own Marathon to participate once free access concludes.
Marathon currently supports cross-play and cross-save across PS5, Xbox Series X|S and PC through Steam. Cross-save requires linked Bungie accounts and ownership of a compatible game version on each platform, while console online play requires the applicable paid subscription.
The Symbiosis update will be available to all Marathon owners on December 8, with the free trial period beginning on the same date.
