The Runner Terminal Item Codex is a complete, searchable database of every item in Marathon — salvage materials, valuables, keys, weapons, mods, implants, cores, and consumables. Every item entry shows its rarity, description, credit value, and a full list of uses — including which faction upgrades require it, which mods or weapons it's compatible with, and where it can be found or bartered.

Looking up an item in the Codex is the quickest way to understand its value before you decide whether to keep it or sell it. High-value salvage like Drone Resin, Arc Capacitors, and Unstable Gel are needed in significant quantities for faction upgrades across multiple factions, making them worth prioritising on every run. Keys unlock specific loot rooms in each zone and can only be used once, so knowing what's behind a door before you use the key helps you decide if it's worth the slot.

To plan which materials to farm based on your current faction upgrade goals, use the Material Finder. For the full faction upgrade trees, visit the Faction Upgrades guide.