Since Bungie launched Marathon, there have been two main camps in the online discussions about the new extraction shooter—those praising the game's PvP focus and those begging for more PvE action. With Marathon's latest update, however, Bungie has introduced a new mechanic to appease those in the latter camp. The C.A.R.R.I. Protocol is a new mechanic that encourages co-operative play, rewarding solo players and cooperative crews for completing objectives and extracting together. The system will reward cooperative players with CyberAcme Commendations, which is a new currency for players to spend in the C.A.R.R.I. Armory, and the rewards will focus on making the game less punishing for new and intermediate players.

CyberAcme Commendations are earned when players complete contract objectives in a crew or when solo players complete contract objectives or extract solo, and bonus Commendations will be rewarded for extracting with other players. The C.A.R.R.I. Armory contains a rotation of weapons, Salvage Crates with Salvage or Reputation, and other upgrades, and there will be daily deals in the armory. The C.A.R.R.I. Protocol will be active starting with Patch 1.0.6 and run until the end of Season 1. In addition to the new rewards, Marathon players will now also have access to Mercy Kit, which is a med kit designed specifically to healed down players not in your squad. The idea is that, if players decide to form an allegiance with another player they've already downed, they can revive the player and turn them into an ally. This depends on proximity chat, which is now easier to use with a new "toggle to open" function that also launches in the same update.