Bungie released a developer diary that walks through Marathon’s Runner Shells, the biosynthetic bodies players will inhabit in the studio’s next first-person extraction shooter. Marathon is set to launch in March 2026, and the studio has been sharing systems and progression details in the run-up to release.
Runner Shells are designed around specific archetypes. Each shell focuses on a role such as intel gathering, combat disruption, or combat healing. The frames use distinctive silhouettes so players can identify a shell’s role from a distance and react accordingly.Customization comes through Cores, Implants, weapons, and mods. Cores are usually tied to a single Runner Shell and can buff or modify that shell’s native ability. Implants are universal. They add stats and a random perk, and higher-tier implants also include a bonus fixed perk.
Bungie gave a concrete example for mobility builds. With the Vandal core players can change the Vandal’s double jump into a triple jump. Implants can then raise base movement speed, jump height, and heat capacity to support that build. For a fuller walkthrough Bungie’s developer diary is available online.
Visual customization options will be shown later, the studio said. For now the focus in the diary is on how cores and implants let players experiment with and combine different playstyles.
Runner Shell archetypes and abilities
Bungie listed each base archetype and a short description of what it brings to a match.
Destroyer
- Archetype: Combat specialist
- Armed with a personal defense barricade, missile systems, and movement thrusters, Destroyer shells are designed to bring the fight to enemy threats.
Assassin
- Archetype: Shadow agent
- Synthetic smoke deployment and camouflage technology allow Assassin shells to plan unseen strikes or take cover during hostile engagements.
Recon
- Archetype: Intel specialist
- Recon shells excel at identifying threats and tracking movements using echo pulses, tracker drones, and holographic footstep trails.
Vandal
- Archetype: Combat anarchist
- Vandal shells traverse ground at incredible speeds, using their advanced movement and knockback cannon to disrupt combat.
Thief
- Archetype: Covert acquisitions
- With enhanced visors and piloted butterfly drone, Thief shells can locate and acquire loot, then use their grapple to push an advantage or make an escape.
Triage
- Archetype: Field medic
- Triage shells help keep themselves and allies alive using deployable healing drones, onboard reboot abilities, and combat buffs.
Rook
- Archetype: Scavenger
- The Rook frame is designed for scavenger mode, a unique way to play Marathon. As Rook, you’ll drop into a match that’s already in progress as a solo player. You won’t be able to bring a loadout, but you also aren’t risking anything, which makes Rook an excellent option for scavengers.
Bungie posted the Runner Shell details on its site and in the developer diary. For the developer blog post see Bungie’s writeup. Bungie’s senior art director Joseph Cross left the studio ahead of launch.
