Marathon introduces Runner Shells as its version of character classes, but they work very differently from traditional role-based systems in other shooters. Instead of locking you into a fixed identity, each shell is a biosynthetic body with a core kit that you then customize through cores, implants, weapons, and mods to push its playstyle in multiple directions.
1. How Runner Shells Work in Marathon
Runner Shells are the foundation of every build in Marathon, but the shell itself is just the starting point. The real power comes from what you layer on top of it, which means two players using the same shell can feel completely different depending on their loadout.
Understanding the system before you pick your main will save you a lot of painful early runs.
Shell Anatomy: Abilities and Traits
Every Runner Shell comes with three types of built-in tools:
- Prime Ability: Your highest-impact skill with a long cooldown, roughly equivalent to an ultimate in other games.
- Tactical Ability: Your main combat or utility tool with a shorter cooldown, used regularly each run.
- Traits (x2): Passive or situational bonuses that are always available, ranging from movement upgrades to intel tools.
Vandal build.
Cores vs. Implants
Both cores and implants modify your Runner, but in fundamentally different ways.
Cores
Cores are shell-specific modifiers that buff or change how your abilities function. You can equip two cores per shell, but you cannot use the same core twice in a single loadout.
Cores come in five tiers: Standard, Enhanced, Deluxe, Superior, and Prestige. Because cores are tied to a single shell, they enable deep specialization within a single archetype.
Implants
Graceful Landings V5 Implant.
Implants are universal upgrades that any shell can use. They grant additional stats plus a random perk, and the highest-tier implants add a fixed bonus perk on top.
For example, the implant Ping+ V5 keeps your pings attached to enemies for a short time after they break line of sight. Combining the right cores, implants, and weapons is how you build a truly optimized Runner in Marathon.
2. Destroyer Shell
Destroyer Shell.
Destroyer is Marathon‘s frontline combat specialist, built for players who want to dictate the pace of a fight rather than react to one. Of all the shells, it is the most straightforward in concept, but it punishes players who treat it as a solo hero class instead of a team anchor.
Destroyer’s Abilities and Traits
| Type | Name | Effect |
|---|---|---|
| Prime | Search and Destroy | Fires homing shoulder missiles at enemies you have dealt sustained damage to. |
| Tactical | Riot Barricade | Deploys a forward-facing energy shield that blocks incoming damage and lets you take contested ground. |
| Trait 1 | Thruster | Dash in any direction, at the cost of heat generation. |
| Trait 2 | Tactical Sprint | Move faster with increased heat gain. |
How to Play Destroyer
Destroyer’s value comes from using Riot Barricade to cross dangerous sightlines so your teammates do not have to. Your role is to absorb pressure, shield revives, and use Search and Destroy to punish enemies who try to rush while you hold ground.
The biggest trap with this shell is playing it for personal kills instead of team enablement. Destroyer needs discipline, not ego.
Your best synergies are Triage, who sustains your pushes, and Recon, who feeds you information on when and where to move safely.
3. Assassin Shell
Assassin Shell.
Assassin is built for players who win fights before they start by stripping information and creating confusion. It is the shell most players think suits them, and the one that collapses the fastest when played with a panic-fire mentality.
Assassin’s Abilities and Traits
| Type | Name | Effect |
|---|---|---|
| Prime | Smoke Screen | Deploys a smoke disc that sends a line of smoke fields forward, blocking vision and disrupting enemy optics. |
| Tactical | Active Camo | Activates temporary invisibility for roughly 12 seconds; breaks when you shoot, take damage, or use a consumable. |
| Trait 1 | Shadow Dive | Drop from a height to slam a smoke disc on impact, instantly deploying a field and negating fall damage. |
| Trait 2 | Shroud | Your shell auto-cloaks when entering smoke and stays invisible for a few seconds after leaving it. |
How to Play Assassin
The best Assassin loop is: smoke first, reposition under Active Camo, take a guaranteed shot, then disappear before the enemy can trade back. A disciplined Assassin player controls when fights happen and when they end, generating panic and confusion rather than brute-forcing gunfights.
Note that Recon hard-counters Assassin: Echo Pulse reveals invisible targets, and Stalker Protocol tracks you through footprint trails after a shield break. If you see a Recon on the enemy squad, adjust your aggression.
The best synergies for Assassin are Recon (for intel on enemy positions) and Thief (to capitalize on the chaos you create).
4. Recon Shell
Recon Shell.
Recon is the information and intel specialist and the shell that decides fights most directly without firing a single bullet. It is designed for players who are comfortable calling shots and leading squad rotations based on their knowledge.
Recon’s Abilities and Traits
| Type | Name | Effect |
|---|---|---|
| Prime | Echo Pulse | Releases sonar pulses revealing players, AI enemies, and even invisible targets nearby. |
| Tactical | Tracker Drone | Deploys a mechanized drone that hunts enemies and explodes on proximity, applying overheat pressure that locks down movement abilities. |
| Trait 1 | Interrogation | Alerts you when an enemy pings you; performing a finisher on a downed Runner pings their entire crew’s location. |
| Trait 2 | Stalker Protocol | Enemies leave glowing holographic footprint trails after you break their shields, letting you track runners who flee. |
How to Play Recon
Recon’s strength is giving your team permission to push safely. Pulse before every rotation, use Tracker Drone to force enemy movement and overheat, and push the moment a shield breaks while Stalker Protocol shows you exactly where they go.
Getting information and not acting on it is just as costly as having no information at all. Recon only works if you communicate: if you are not calling positions aloud, you are not winning with this shell.
Best synergies are Destroyer (for clean, covered entries) and Assassin (to weaponize your intel with precision ambushes).
5. Vandal Shell
Vandal Shell.
Vandal is Marathon‘s movement disruptor, built for players who use speed and positioning to break enemy formations and force panic. It is not a pure movement shooter shell, but it rewards anyone who can chain its mobility tools without overheating.
Vandal’s Abilities and Traits
| Type | Name | Effect |
|---|---|---|
| Prime | Amplify | Temporarily boosts movement speed, weapon handling, and heat efficiency, letting you chain movement actions without overheating. |
| Tactical | Disruptor | Fires a chargeable energy blast with knockback; can also be aimed downward to launch yourself airborne for repositioning. |
| Trait 1 | Microjets | Grants a double jump at the cost of additional heat. |
| Trait 2 | Power Slide | Extends slide distance and speed, again at the cost of heat generation. |
How to Play Vandal
Vandal’s biggest risk is heat mismanagement. Overuse your movement tools, and you go from a disruptor to a sitting duck in seconds. Use Amplify intelligently to chain movement and force enemies to chase and separate, then use Disruptor to blast them out of cover or knock a runner into a bad position.
Bungie has confirmed mobility-focused cores for Vandal, including jump enhancements and movement chaining, that massively raise the ceiling of this shell once you acquire them.
The best synergies for Vandal are Destroyer to anchor fights and Thief to pair chaotic movement with efficient looting in the wake of the chaos.
6. Thief Shell
Thief Shell.
Thief is the loot acquisition and covert extraction specialist, quietly one of the strongest shells for players who prioritize the economy layer of Marathon over raw combat. Its kit doubles as both a loot vacuum and a makeshift reconnaissance tool, giving it unusual flexibility.
Thief’s Abilities and Traits
| Type | Name | Effect |
|---|---|---|
| Prime | Pickpocket Drone | Deploys a remote-controlled origami butterfly drone with a mechanical whip that knocks loot from enemies and collects dropped items; can also fly ahead to ping nearby enemies for your squad. |
| Tactical | Grapple Device | Fires a forearm dart that unfolds into a self-propelled propeller, pulling you forward from anywhere, including open air where no attachment point exists. |
| Trait 1 | X-Ray Visor | Flip-down visor reveals loot containers through walls with their rarity highlighted; also marks enemies within your direct line of sight. |
| Trait 2 | The Finer Things | Your grapple recharge rate, weapon handling, and base stats increase as your backpack fills with more loot. |
Confirmed Thief Cores
Bungie has revealed several Thief cores that showcase how far this shell can be pushed:
- Greed is Good (Enhanced): When your backpack is full, sprint speed and slide distance increase.
- Hidden Run (Deluxe): Striking an enemy with a melee or knife immediately after grappling hacks them and knocks random loot from their backpack.
- Case the Joint (Superior): Your X-Ray Visor gains increased vision range through walls.
- Partner in Crime (Prestige): While not being piloted, your Pickpocket Drone periodically releases a pulse that pings nearby hostiles.
- Second Grapple: Grants a second charge of your Grapple Device.
How to Play Thief
The key mistake Thief players will make is spending too long piloting the drone while stationary in a contested zone. Fly it only when your squad has your back, scan loot routes, and grapple out early rather than overstaying for one extra item.
Best synergies are Vandal to generate distractions that let you loot safely and Assassin to provide clean exits and keep enemy vision suppressed during your runs.
7. Triage Shell
Triage Shell.
Triage is Marathon‘s field medic and team-sustain shell, and it carries some of the most underrated abilities on the entire roster. Played correctly, it flips losing fights into recoveries that catch enemy squads completely off guard.
Triage’s Abilities and Traits
| Type | Name | Effect |
|---|---|---|
| Prime | Capacitive Gauntlets | Charge and fire electric tendrils at range to either zap enemies or revive downed teammates without being next to them. |
| Tactical | Med Drone | Sends a drone to hover over you or an ally’s shoulder, providing continuous health and shield regeneration. |
| Trait 1 | Battery Overcharge | Overcharges your weapons, causing them to EMP targets when you break their shields. |
| Trait 2 | Shareware | Any ally with a Med Drone attached also receives copies of any consumables or heals you use, remotely extending your sustain to teammates. |
Confirmed Triage Cores
Triage’s revealed cores deepen both its offensive and support potential:
- High Voltage (Enhanced): Defeating hostiles affected by EMP reduces your next Battery Overcharge cooldown.
- Electron Recapture Syncs (Deluxe): While Battery Overcharge is active, defeating a hostile or downing a Runner with a vault weapon instantly restores a portion of that weapon’s charge.
- No Good Deed (Superior): You receive a burst of healing when your Med Drone successfully attaches to a crew member.
- Samaritan (Prestige): Sharing a consumable via Shareware reduces your next Med Drone cooldown.
How to Play Triage
Triage is built entirely around team proximity and Med Drone uptime. Stay close to your squad, prioritize keeping the drone attached during dangerous phases, and use Capacitive Gauntlets to deliver range revives instead of exposing yourself.
Playing Triage as a lone wolf actively hurts your team by wasting the shell’s entire value proposition.
Triage works best when paired with Destroyer (who pushes forward while you provide sustain behind) and Recon (who feeds you intel on when your teammates are in danger and when it is safe to reposition).
8. Rook: The Scavenger Shell
Rook Shell.
Rook is not a standard Runner Shell. It is a stripped-down scavenger frame designed exclusively for players who want to join matches with zero risk and zero loadout. Rook drops into raids that are already in progress as a solo player, bringing nothing in and therefore losing nothing if eliminated.
How Rook Works
Because Rook joins mid-match with only a starter kit, it enters every raid at a disadvantage compared to properly geared Runners. The upside is that the risk-reward equation flips entirely: there is no gear to lose, making Rook ideal for learning the maps, practicing loot routes, or recovering items from a rough previous run.
| Type | Name | Effect |
|---|---|---|
| Prime | Recuperation | Activates your prototype frame’s emergency repair system, slowly regenerating your health. |
| Tactical | Signal Mask | Activates a mask that makes UESC AI forces treat you as non-hostile, letting you move through AI-heavy zones without being attacked. |
Blend is Rook’s key survival tool, letting you slip through AI-controlled zones undetected while geared Runners fight around you.
However, other players can still see and kill you. Approach every match as Rook, assuming you are a target.
