Echo

That extra teammate might not be your teammate.

Echo adds a separate enemy to R.E.P.O. It disguises itself as a randomly selected active player, explores rooms, briefly joins the group and waits for an opportunity to sprint in, headbutt someone, then run away. It can also help with a loaded unattended cart before stealing it, preferably when nobody is watching.

Early release for R.E.P.O. 0.4.4.3. Every player needs Echo 0.9.5 and its dependencies.

What Echo does

Copies a random available player, not just the host: appearance, name and voice identity stay linked. One compatible head-accessory slot differs, chosen from the game's registered catalogue (hats, ears, eyewear, face/head accessories and compatible overlays). A host-generated random seed is shared with clients, rather than deriving the tell from regularly spaced network IDs. Body, tools and base head/eye meshes are not replaced. If no replacement is compatible, one safe head accessory is removed instead; if neither is possible, the avatar stays visible and logs a warning. A finite catalogue can repeat.
Carries its own render-only stock flashlight, aimed with Echo's animated arm and gaze. Its back display shows Echo's own health.
Uses player-style walking, sprinting and Q-like tumble animations with a physical body.
Prefers independent exploration and other rooms, leaves more personal space and has a cooldown between brief periods of company. Retreat routes score actual path corners, distance to the pursuer along the path, cover and clearance, not just a distant endpoint.
Chooses surprise headbutts and, when possible, approaches that point toward measured drops or death pits. The default headbutt applies teammate-style knockdown rather than a flat HP penalty; falls and hazards can still hurt.
A missed or countered committed headbutt retains its retreat plan. Physical tumble/carry time does not consume the escape window; stalled escape routes are replanned. The run-up includes a short preparation and minimum sprint window.
Opens suitable physical hinged doors, takes weapon/object damage and has 80 HP. Actual HP loss causes its own red flash and spatial player-hurt sound; copying a player's injury or receiving a healing update does not. It can be healed using its back handle, at the donor's HP expense.
Can be grabbed and carried while tumbling, including after its own dive or your incoming sprint-Q hit.
Occasionally helps with, then steals, a loaded large cart. Any valuables qualify; higher-value carts are preferred. After three seconds of help it prefers an unwatched opening, but after eight seconds it can prepare a bold theft even while watched. Short collision-checked segments can continue/replan instead of requiring one long straight lane; the theft is bounded to twelve seconds. When exposed while gripping, it tries to escape with the cart. A real player's grab takes priority. Small carts and carts inside the truck are excluded.
Automatically repeats short snippets of the copied player's voice, unless replay is disabled. No activation key or opt-in prompt is required.
Seeing its copied original in the same room triggers a retreat after a brief glimpse, including solo. Recognition uses the game's actual room volumes, not a twelve-metre radius through adjoining rooms. Only a two-second initial grace remains; the original need not look back. Walls block recognition. Echo avoids returning immediately and can continue retreating while pursued in the same room.
Nearby receptive monsters notice visible, moving or speaking Echoes, including stationary close encounters. Hunter can use its native investigation/aim/fire path; Runner, Slow Walker and Robe can start native position-directed melee attacks at close range. Robe now progresses from investigation to its real windup/swing instead of repeatedly investigating at Echo's feet. Its swing aims at Echo's selected position rather than an old player target. Existing active hitboxes hurt/knock Echo down. Active chases/attacks on real players are not hijacked; this does not reproduce every monster's player-specific grabs or special attacks.

The original Reaper and other enemies are not replaced. Echo joins normal enemy selection when Spawning/NaturalSpawns is enabled (default). By default, level 1 has no natural Echo; Echo becomes eligible from displayed level 2, with relative selection weight 70 (previously 35). This is not a 70% chance per level and does not guarantee an Echo every round: the game's enemy budget and other eligible enemies still matter.

Install and play

Install through Thunderstore Mod Manager or r2modman with dependencies, then launch Modded. Use the same Echo version on every client. Dependencies are BepInExPack 5.4.2305 and REPOLib 4.2.0; their DLLs are not bundled inside Echo.

For manual installation with dependencies already installed, copy the ZIP's BepInEx folder into your modded profile/game folder. Do not install a second copy of RepoEnemyMod.dll elsewhere.

Configuration is created after first launch at BepInEx/config/robin.repoenemymod.cfg. Settings include natural spawning, friendly wait, attack interval, player-like impact, hazard ambushes, cart sabotage and voice replay. Restart after editing config outside the game.

Spawning/MinimumSpawnLevel defaults to 2; Spawning/NaturalSpawnWeight defaults to 70 (zero disables selection). These are applied on the next level generation. Echo uses the available early-game enemy pool until the normal difficulty-2 pool has slots, without increasing the total enemy count.

Natural encounters and manual spawning

Play normally from level 2 onwards. The built-in F6 spawn key and F7/F9/F10/F11 testing shortcuts have been removed. Old Testing/SpawnKey and Testing/ClearKey settings are ignored. No extra Echo is force-spawned at the start of a round.

F3 manually spawns one Echo nearby. This shortcut is included in the release for now. Use it as the host during active gameplay, with menus/chat closed and clear floor nearby. It also works on level 1, but pressing F3 is required; it does not enable automatic level-one spawns. Everyone must have the same Echo version. An on-screen message explains placement or compatibility failures.

For manual testing with the optional REPO Command Console, open F2 in a generated gameplay level and use /spawn enemy:Echo 1 player-location. Echo remains in that catalogue on level 1 and when natural spawns are disabled. Manual spawning still requires the host and matching Echo versions on every client. The console is not bundled or required for normal play.

There is no voice activation or toggle hotkey. F8 no longer changes Echo's voice replay.

All clients must have the matching Echo version before it can be selected or spawned. If one participant is missing the mod or using an older version, Echo is excluded to avoid incompatible prefab spawning.

Voice: automatic, temporary, no AI cloning

Voice replay is automatic. Speak normally, then pause; Echo can reuse remembered snippets when disguising itself as you. It preferentially responds in a short gap after another audible participant speaks, using the copied player's voice, with a less frequent same-speaker/solo response. It detects speech timing, not meaning: responses are not generated conversations. No opt-in prompt, permission button or activation key is required. The old AllowOwnVoiceReplay and DisableOwnVoiceReplay personal-toggle settings are obsolete and ignored in 0.9.1. The whole-feature troubleshooting setting Echo.Voice/EnableVoiceReplay=false still disables capture/replay on your client; that disabled state is respected by peers. Normal microphone mute and push-to-talk remain effective.

Multiplayer reuses the game's existing local voice recorder and received Photon voice streams; it does not start a second microphone. In solo, Echo automatically opens the microphone selected in the game's settings while you are in a generated gameplay level, because there is no multiplayer voice stream. Solo capture stops and clears when disabled or when leaving the level, and respects the game's mute/push-to-talk settings. A visible status box shows when solo capture is active. Echo does not bypass microphone permissions or unmute anyone.

Echo keeps at most sixteen completed clips of up to three seconds per speaker, for up to eight speakers. A recent bank plus a sampled older bank preserves more variety; it is not a complete recording of everything said. Clips expire after eight minutes, remain in RAM and are cleared on session/disable cleanup. Already played clips have a repeat cooldown, and Echo playback cannot trigger a chain of Echo replies. There is no speech generation, AI voice cloning, transcription, audio-file storage or upload of stored clips. Each client plays from its own received snippets, so different players may hear a different phrase or none if they did not receive usable speech. Existing normal multiplayer voice traffic is unchanged.

Known limits and troubleshooting

Version 0.9.5 passed builds, focused room-recognition/Robe-attack policy checks, the existing pure regression suite, reflected-member validation and package checks. No new live game run was performed for this update. The shared appearance seed changes Echo's network payload relative to older releases: update all clients together. The older live-test results below are historical, not live verification of this update.

Solo gameplay, loading, player-like headbutts, counter-Q, physical interactions, identity and a private lobby with one real host have been checked during development. An actual second-client session and real multiplayer microphone replay have not been fully verified. This is an early release, not a guarantee of perfect player imitation or compatibility with every other mod/game update.

The 0.9.0 update was tested on 16 September 2026 in fresh isolated solo rounds and a private lobby with one real host. Checks include player rendering/animations, sprint-Q and escape, incoming Q and recovery, carrying, weapon/object damage with its own hurt-flash/sound event, healing, physical doors, copied-name visibility and lobby/round/menu transitions. A normally spawned loaded cart was physically pulled over three metres; native player grabbing and sprint-Q interrupted its grip. Combat/cart tests deliberately arrange an open corridor; they do not measure natural spawn frequency or guarantee behavior in every room. Voice playback/revocation used muted synthetic PCM, not a real microphone. Automated behavior, cosmetic, cart, voice-memory and timing checks also pass. Full two-client voice and every monster's reactions still need live multiplayer acceptance testing.

No natural spawn: level 1 is excluded by default. Check every client's version/dependencies and Spawning/NaturalSpawns. Echo is one possible selection, not a guaranteed encounter. Manual F2 testing is independent of the natural level restriction.
No speech: the copied speaker needs to say a short audible phrase, then pause; check microphone, mute/PTT and EnableVoiceReplay. Empty voice memory cannot produce speech. Automatic replay is not an AI conversation system.
No attack/cart interaction: reachability, observers, cart contents, player grabs and nearby geometry can prevent a plan.
For other errors, check the active profile's BepInEx/LogOutput.log. Include Echo, game and dependency versions when reporting a problem. Review logs for private details before sharing them.

Independence and credits

Echo has its own plugin and configuration and can be installed without Gamba. This package contains only the Echo plugin and page metadata/icon: no Unity editor project, game assemblies, extracted game models, saved games, voice recordings or debug plugins. Player visuals and animations are referenced from the user's installed game at runtime.

R.E.P.O. and its original assets belong to semiwork. Thanks to the BepInEx and REPOLib maintainers. This is an unofficial community mod, not an official semiwork release.