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Cepheus Protocol
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.
Recent Reviews:
Mixed (41) - 68% of the 41 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (2,287) - 81% of the 2,287 user reviews for this game are positive.
Release Date:
15 May, 2020
Developer:
Publisher:
Halcyon Winds

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Features
Languages:
Interface Full Audio Subtitles
English ✔ ✔
Simplified Chinese ✔
Korean ✔
German ✔
Japanese ✔
Russian ✔
Spanish - Spain ✔
Portuguese - Portugal ✔
French ✔
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Includes 5 Steam Achievements
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all 5
Points Shop Items Available
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Awards
Best Horror Award at Dreamhack Anaheim 2020

Early Access Game

Get instant access and start playing; get involved with this game as it develops.

Note: Games in Early Access are not complete and may or may not change further. If you are not excited to play this game in its current state, then you should wait to see if the game progresses further in development. Learn more

What the developers have to say:

Why Early Access?

“Cepheus Protocol is an ambitious game still in development. While there will be bugs and issues, we hope you’ll join us in actively providing feedback. If you’re not ready to jump in yet, we completely understand and hope you’ll consider supporting us once the game leaves Early Access.

How often do we update?
We release minor bug fixes and general updates regularly—at least once a week, sometimes more. Hotfixes are deployed as needed, especially when our community identifies issues that affect gameplay. Significant updates are released every month or two, including through our experimental build on Steam. These experimental builds allow the community to test new mechanics and systems without affecting the main game. Once deemed stable and polished, these updates are rolled into the core game, where we continue refining them based on feedback.

Major Updates:
Larger updates, such as builds 1.0, 1.1, 1.2, and beyond, take longer to complete. Each build focuses on different aspects of gameplay, systems, and mechanics, such as civilian management, dynamic civilian groups, new zones (e.g., San Francisco), animations, weapons, vehicles, and character models. As we are a small team, sometimes only one person works on these features, which can extend timelines. Despite this, we always provide previews of our work, including live developer streams on Discord to keep our community informed.

Community Involvement:
As a major update nears completion, we invite the community to test and review these changes in the experimental build. After a few days or weeks of feedback collection, we assess what fixes or adjustments are needed before releasing updates publicly. Our internal testing aims to address significant issues before they reach players, but community feedback remains critical to this process.

Minor Updates and Bug Fixes:
We strive to address bug fixes quickly, although timelines may vary depending on the severity of the issue and the availability of our team. If fixes take longer than expected, we keep the community informed and express our gratitude for their patience and support.

Challenges and Development Impacts:
Unforeseen challenges—such as engine updates, learning new software, developer illness, or team changes—can affect our progress. Despite these obstacles, we remain committed to keeping Cepheus Protocol on track and maintaining open communication with our community.”

Approximately how long will this game be in Early Access?

“We plan to stay in Early Access as long as needed to achieve our vision for Cepheus Protocol. Our tentative goal is to leave Early Access in 2025, but this depends on the resources available to our small team and the complexity of the remaining work.

Our focus is on delivering a polished, feature-complete game, so the timeline will remain flexible to ensure the best possible result. Your support and feedback during Early Access are vital to helping us achieve this goal.”

How is the full version planned to differ from the Early Access version?

“The full version of Cepheus Protocol will feature the following: Pandemic Mode, which is the current iteration of the game that is playable now. Story/Campaign, co-op, Horde Mode, and Special Operations.”

What is the current state of the Early Access version?

“The Early Access version of Cepheus Protocol provides a solid and evolving experience focused on Pandemic Mode, where players manage squads to contain and combat a rapidly spreading infection. Key features include:

  • Core Gameplay: Squad-based real-time strategy with dynamic enemy AI, base building, and resource management.
  • Playable Content: A sandbox mode featuring diverse enemy types, squad abilities, and engaging objectives.
  • Iterative Updates: Regular additions of new features, refinement of existing mechanics, and bug fixes driven by community feedback.
  • Experimental Builds: A dedicated test environment on Steam where players can preview and provide feedback on new mechanics, animations, and systems before they are integrated into the main game.
  • Active Development: AI behavior, animations, and core mechanics are continually improved. While the game is stable and enjoyable, occasional bugs and performance issues may still occur as we work to polish the overall experience.
”

Will the game be priced differently during and after Early Access?

“The price of the game will increase when it leaves Early Access. The exact new price will be determined closer to the full release. We will inform our community in advance of any price changes.

Those who purchase the game during Early Access will not incur additional costs when the game is fully released, as their copy will automatically update to the release version.

However, we plan to continue supporting the game post-launch with optional additional content, such as DLCs, skins, special items, and other related content. These updates will be separate from the main game and will not be included for free with Early Access purchases.”

How are you planning on involving the Community in your development process?

“
  • Feedback-Driven Development: Players can share their thoughts, bug reports, and suggestions through forums, social media, and our Discord server. This feedback helps shape gameplay adjustments, feature priorities, and overall improvements.
  • Experimental Builds: New mechanics, systems, and content are first released in an experimental build on Steam, where the community can test and provide input without affecting the main game. This helps us refine features before public release.
  • Transparency: We keep our players informed about ongoing development through regular updates, patch notes, developer live streams, and behind-the-scenes previews on Discord and other platforms.
  • Iterative Updates: As we receive feedback from the community, we continuously iterate on systems and features to align the game with player expectations.
”
Read more
Check out the entire Cepheus Protocol Franchise on Steam
 
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Reviews

“A game that caught me off guard with how freaking fantastic it is, it runs fairly darn well, is pretty intense and reminds me quite a bit of They Are Billions just in a more modern world.”
SmashGaminG

“I'm really into Tower Defense games and this one is a great creation. It keeps you easily entertained. The sounds and graphics are decent. It's still in E.A and it looks pretty good so far.”
~8.2/10 – Kawaii Reviews

“Cepheus gameplay is a unique blend of RTS with a real tower defense feel. 100% a strong learning curve to master the tactical skills layered across the six different character classes. Check it out!”
Mature Minded Gamers

Special Announcement: Opt Into Cepheus Protocol Experimental Builds

Be the first to experience cutting-edge features and updates by opting into Cepheus Protocol Experimental Builds!

What You'll Get:

  • Early access to new gameplay mechanics, systems, and features.

  • A chance to provide feedback that shapes the future of Cepheus Protocol.

  • A sneak peek at upcoming content and improvements before they hit the main build.

How to Opt-In:

  • Buy/Own the Base Game of Cepheus Protocol

  • Go to your Steam Library.

  • Search for Cepheus Protocol Experimental Branch.

  • Install and have fun!

Roadmap

Explore the future of Cepheus Protocol! Discover upcoming features like Doctrines, the DNA Research System, Operator Units, and Co-op Mode. Stay informed with all updates by visiting our full roadmap on our website.

About This Game

An Open World RTS Military Survival Game. Command CERC (Center for Epidemic Research and Control) to stop a pandemic-level event from consuming the Bay Area. The Pangu Virus threatens humanity as it spreads, turning native inhabitants into infected, relentless swarms. Can you adapt, survive, and reclaim control?

Hardcore RTS Military Combat Meets Survival Horror

  • Aircraft Carrier Operations
    Your mobile base of operations in Pandemic Mode. If it’s destroyed, you lose. Defend it at all costs and utilize Winters, now a rebuildable hero, to lead your forces.

  • A New Threat Rises
    Battle infected hordes that can infect and turn your own units. Command land, sea, and air forces to hold the line in this unforgiving world.

Dynamic Gameplay Systems

  • Command the Operator
    Control the battlefield in Third-Person Shooter mode or use the Operator as a hero unit in RTS mode. Adapt your strategies to survive.

  • Doctrine Tree Progression
    Unlock new support options, powerful weapons, and unique units by leveling up through the Doctrine tree.

  • Customize Pandemic Mode
    Create your perfect challenge. Turn off infected types, adjust gameplay options, and create custom scenarios to tailor the experience.

  • Character Progression
    Improve your characters’ health and targeting efficiency as they gain experience through combat.

Innovative Mechanics and Features

  • Line of Sight and Hearing AI
    Experience cutting-edge AI that hunts your units based on what they can see and hear. Stay stealthy, or face overwhelming swarms.

  • Massive, Detailed Maps
    Explore sprawling urban environments filled with varied locales. Plan every attack, defense, and civilian evacuation carefully to ensure survival.

  • Dynamic Civilian Diplomacy
    Interact with rogue civilian groups. Recruit them to your cause, negotiate alliances, or defend yourself from hostile factions.

  • Civilian Evacuation
    Manage who lives and dies with an intricate Civilian Administration Structure. Customize your intake system or use preset templates to make critical decisions.

Destroy the Infection

  • Research the Pangu Virus
    Delve into the secrets of the alien pathogen and find a way to kill Patient 0 before it’s too late.

  • Hunt Patient 0 and Their Lieutenants
    Stop the infection from spreading by targeting its leaders. Destroy their expanding hordes before they consume every province.

  • Dynamic Provincial Events
    Encounter unexpected challenges as rogue civilian combatants and infected groups form dynamically across the map. Your reputation and decisions will shape the world around you.

Planned Features

  • Enhanced Operator Customization
    Tailor weapons, abilities, and appearance. Drive vehicles, gain progression perks, and refine your playstyle for maximum impact.

  • DNA Research System
    Develop a proper progression tree to counter the virus, protect your units, and evolve your strategies.

  • Improved AI Logic
    Refine the behavior of infected Lieutenants and AI to challenge extreme turtle strategies.

  • Co-Op Multiplayer
    Share control of CERC operations with up to four players. Pool resources, coordinate tactics, and fight as a team against the infection.

  • Canon Campaign Mode
    Experience the official Cepheus Protocol story, inspired by the novel and side storie

Mature Content Description

The developers describe the content like this:

This Game may contain content not appropriate for all ages, or may not be appropriate for viewing at work: Frequent Violence or Gore, General Mature Content

System Requirements

    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 2 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
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What Curators Say

64 Curators have reviewed this product. Click here to see them.

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