Out now · Early Access

Cepheus Protocol

Developed by Halcyon Winds · Published by Halcyon Winds

ActionAdventureIndieMassively MultiplayerRPGSimulationStrategy
StatusOut now · Early Access ReleaseMay 15, 2020 Price$15.99 Steam reviews2,875

At a glance

PlatformsWindows
ModesSingle-player, Multi-player, Co-op, Online Co-op
Price$15.99
StatusOut now · Early Access
Early accessYes
Steam reviews2,875
Languages9
Achievements5
DLC7

Overview

An action, adventure, indie game by Halcyon Winds, published by Halcyon Winds — single-player, multi-player, co-op, online co-op. It is in Early Access.

Steam’s own one-line description: “Cepheus Protocol is an Open World RTS Military Survival Game. Play as the CERC hunting Patient 0, maintain Quarantine camps, fight dangerous mutations & Rogue Civilian Combatants . There’s nobody else coming, it’s up to you now.” — developer/publisher text via the Steam store page.

Reception & community

Steam reviewsMostly Positive — 79% positive of 3,032
Owners (est.)200000 – 500000
Peak players20
Player-voted tags:SandboxZombiesRTSSurvivalPost-apocalypticBuildingStrategyGoreOpen WorldSingleplayerDiplomacyIndie

Review sentiment, ownership and peak-concurrent estimates via SteamSpy; tags are player-voted on Steam. Estimates change over time.

Features & modes

Derived from the gameplay modes and feature categories Steam lists for Cepheus Protocol.

FeatureSupported
Single-playerYes
MultiplayerYes
Co-opYes
Online co-opYes
PvPNo
Cross-platform multiplayerNo
Full controller supportNo
Partial controller supportYes
Steam Cloud savesYes
Steam AchievementsYes

System requirements (PC)

As published on the Steam store page. Requirements can change between updates.

Minimum

  • Requires a 64-bit processor and operating system
  • OS: Windows 10/11 (64-bit)
  • Processor: Intel® Core™ i5-4500K
  • Memory: 8 GB RAM
  • Graphics: NVIDIA GeForce 1060 GTX or AMD Radeon Equivalent 4 GB
  • DirectX: Version 12
  • Storage: 8 GB available space
  • Sound Card: Direct X Compatible
  • Additional Notes: **recommended SSD install for optimal performance

Recommended

  • Requires a 64-bit processor and operating system
  • OS: Windows 10/11 (64-bit)
  • Processor: Intel® Core™ i7-6770K / AMD Ryzen 5 1500X
  • Memory: 16 GB RAM
  • Graphics: NVIDIA GeForce 2060 GTX or AMD Radeon Equivalent 6GB VRAM
  • DirectX: Version 12
  • Storage: 8 GB available space
  • Sound Card: Direct X Compatible
  • Additional Notes: **recommended SSD install for optimal performance

Supported languages (9)

EnglishSimplified ChineseKoreanGermanJapaneseRussianSpanish - SpainPortuguese - PortugalFrench

Cepheus Protocol FAQ

Answered from the official Steam listing as of June 2026. Where something hasn't been announced, we say so rather than guess.

What kind of game is Cepheus Protocol?

Steam classifies Cepheus Protocol as a Action, Adventure, Indie, Massively Multiplayer, RPG, Simulation, Strategy game, developed by Halcyon Winds. Cepheus Protocol is an Open World RTS Military Survival Game. Play as the CERC hunting Patient 0, maintain Quarantine camps, fight dangerous mutations & Rogue Civilian Combatants . There’s nobody else coming, it’s up to you now.

How much does Cepheus Protocol cost?

As of June 2026, Steam lists Cepheus Protocol at $15.99. Prices and regional pricing change — check the Steam page for the current figure.

Is Cepheus Protocol single-player or multiplayer?

Steam lists these modes for Cepheus Protocol: Single-player, Multi-player, Co-op, Online Co-op. It supports both solo and multiplayer.

Is Cepheus Protocol on PlayStation, Xbox, or Switch?

Our data comes from the Steam (PC) store, which lists Cepheus Protocol for Windows. Console availability isn’t in our Steam-sourced data — check the official site or the console store.

Is Cepheus Protocol out yet?

Yes — Steam lists a release date of May 15, 2020.

What platforms is Cepheus Protocol on?

Cepheus Protocol is listed for Windows on the Steam (PC) store. Console availability isn't covered by Steam's PC store data — check the official channels.

Is Cepheus Protocol single-player or multiplayer?

Steam lists these modes: Single-player, Multi-player, Co-op, Online Co-op.

How much does Cepheus Protocol cost?

Steam lists it at $15.99.

Does Cepheus Protocol have achievements?

Yes — Steam lists 5 achievements for Cepheus Protocol.

Who made Cepheus Protocol?

Cepheus Protocol is developed by Halcyon Winds and published by Halcyon Winds.

Where to get Cepheus Protocol

We don't sell games or track prices — this links to the official Steam store page.

View on Steam →

Listing details from Valve's public Steam store data · official site. Not affiliated with Valve/Steam, Halcyon Winds.