The Callisto Protocol Cheats & Secrets guide screenshot

Cheats & Secrets

Cheats & Secrets for The Callisto Protocol



Overview



The Callisto Protocol does not include traditional cheat codes, developer console commands, or unlockable cheats (like invincibility or infinite ammo). The game is designed as a challenging survival horror experience with no official Cheat mode. However, there are several legitimate secrets, hidden content, Easter eggs, and unlockable features that a player can discover. This guide covers all known developer-intended hidden content, collectible rewards, and gameplay secrets.

> Note: Glitch exploits (e.g., infinite ammo duplication, skip mechanics) exist but are not covered here as they can cause save corruption or softlocks. Only safe, reproducible secrets are listed.

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Unlockable Content & Rewards



#### New Game+
  • How to Unlock: Complete the game on any difficulty. After the credits, you will be prompted to start a New Game+.

  • What Carries Over: All weapons, weapon upgrades, GRP upgrades, health injectors, and currency (Callisto Credits).

  • Exclusive Feature: New Game+ adds a Secret Ending achievement if you collect all 37 Audio Logs and all 39 Biophage Lore files across the playthrough. (See below.)


    • #### Hardcore Difficulty
  • How to Unlock: Beat the game on Maximum Security (the hardest default difficulty).

  • Differences: Enemies deal more damage, Jacob takes more damage, resources are scarcer, and checkpoints are fewer. No other hidden difficulties are unlockable.


    • #### Secret Ending (Collectible Reward)
  • Requirement: Collect all 37 Audio Logs and all 39 Biophage Lore files in a single New Game+ save file (or in the same playthrough if you 100% the base game and continue NG+).

  • What It Is: A post-credits scene showing a mysterious figure (potentially setting up a sequel) that is not shown in a normal playthrough.

  • Note: This is the only narrative secret in the game.


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    Easter Eggs & Hidden References



    #### "That's No Moon" - Dead Space Reference
  • Location: Chapter 8 – Below the habitat dome, you can look up at the shattered moon of Callisto. If you angle the camera just right, the moon resembles the Brethren Moons from the Dead Space series. This is a direct nod to the game's spiritual predecessor.

  • How to See: During the outdoor section after the tram crash, stop and rotate the camera upward toward the moon. The silhouette is intentionally shaped.


    • #### "You Are Dead" Screen (Dead Space Callback)
  • Location: Any death in the game after being killed by a Biophage's grab attack. Instead of the normal death animation, sometimes the screen flashes with the words "YOU ARE DEAD" in red, mimicking the death screen from Dead Space. This is not guaranteed—appears more frequently on Maximum Security difficulty.


    • #### Two-Headed Monster (Secret Enemy)
  • Location: Chapter 9 – After the autoclave sequence, in a side room that is easy to miss, you can find a unique Biophage variant with two heads. It has more health and deals more damage. It does not respawn.

  • How to Access: Just before the final arena with the giant tentacle, look for a door labeled "Incinerator". Inside, the Two-Headed Monster spawns.


    • #### Hidden GRP Upgrade (Secret Weapon Enhancement)
  • How to Get: In Chapter 6, after unlocking the GRP (Gravity Restraint Projector), go back to the Med Bay area. In the room where you first fought the blind Biophage (the spitter), there is a broken vending machine. Interact with it repeatedly (3 times) to receive a GRP Capacitor Upgrade that increases the force and recharge rate.

  • Note: This is not marked on the map and is easy to miss. It only works if you have the GRP already.


    • #### Developer Room (PC Exclusive)
  • Platform: PC version only.

  • Method: At the main menu, press `~` to open the console (if supported—some updates removed it). Type `open devroom` to warp to an unfinished developer test room. This room contains various weapon models, unused enemy types, and a few collectibles. Use at your own risk—this can break your save file if you save inside.

  • Tip: Do not save in the dev room; just explore and exit via the console command.


    • #### "Hello World" Hidden Message
  • Location: In the first chapter (Jacob's crash site), immediately after regaining control, look at the bottom of the tram terminal screen. A tiny text reads "HELLO WORLD" in retro font. This is a nod to the developer Striking Distance Studios' first game.


    • #### Secret Audio Log in Chapter 1
  • How to Find: In the morgue at the very start (before you get the handcuffs), open the first drawer on the left three times. It will glitch open and reveal a hidden Audio Log titled "Prisoner 847's Last Words". This log is not counted in the collectible tracker because it is a bonus Easter egg.


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    Glitch-Free Exploits (Safe to Use)



  • Ammo Conservation Trick: If you aim a weapon with a burst fire mode and quickly swap weapons before the burst ends, the remaining bullets are refunded. This works with the Skunk Gun (pistol) and Riot Gun. It is not a cheat but a design oversight that does not break progression.

  • GRP Recharge Exploit: Hold the GRP on an enemy and release just as the charge depletes; the GRP recharges instantly. This is very useful for crowd control.

  • Crate Duplication (Minor): In a few places, you can smash a crate, run away, come back, and the crate reappears, dropping resources again. This is inconsistent but known to happen in the Echo area (Chapter 4).


> All above exploits are safe and will not corrupt your save or disable achievements.

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Summary



The Callisto Protocol rewards exploration and completion with a secret ending and a few hidden upgrades. While there are no codes to type or buttons to press for invincibility, the game's world is filled with small secrets that enrich the lore and gameplay. Always check corners, interact with things twice, and listen for audio cues—there is usually more than meets the eye.