A regularly updated, brutal open-world real-time strategy game, you're tasked with finding patient zero before an alien virus takes over San Francisco. Command your squad, defend your base, and stop the Pangu virus. Inspired by games like Company of Heroes, World in Conflict, and XCOM.
Recent Reviews:
Very Positive (18) - 94% of the 18 user reviews in the last 30 days are positive.
All Reviews:
Very Positive (206) - 90% of the 206 user reviews for this game are positive.
Release Date:
May 15, 2020

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Early Access Game

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

Note: This Early Access game is 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?

“We’re extremely proud of what the team has built so far and are eager to continue the development of the game. Launching in Early Access means it’ll provide us with enough financial stability to keep developing Cepheus Protocol. Most importantly, this also means that we can get feedback and suggestions from players so that we can improve the game and get it to its final and optimal state.”

Approximately how long will this game be in Early Access?

“We plan to be in Early Access for 1 year with a target release date of Q2 2021.”

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

“The final version will include a Campaign mode, additional weapon types, enemies, and more. In addition, Early Access will allow us to polish the game further including higher quality textures and world-building.”

What is the current state of the Early Access version?

“You'll build bases, recruit new soldiers, and send teams out in the field to battle the growing virus, all the while hunting down Patient Zero is the primary goal of the CERC(You). With replayability and challenging gameplay at its core, players must be mindful of the environment and the changing nature of the battlefield. Each soldier's loss is a man not easily replaced.

You'll have to use all the tools in your arsenal to research the plague and seek out Patient Zero, whose mastery over the virus grows with each victim she infects. Stopping her is paramount, or a city of millions could be lost.”

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

“We plan to gradually raise the price as we ship new content and features.”

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

“Communication with our community is our top priority – it’s one of the main reasons why we wanted to launch in Early Access. We want to talk to you and hear your questions, concerns, suggestions, and feedback. You can reach out to us on social media (Twitter, Instagram, and Facebook), on Steam, and by email at info@halcyonwinds.com.”
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“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.”

“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

Just Updated

  • Engineers and Vehicles - Are now live and buildable!
  • Improved AI - will now actively seek to flank and surround you. Pods will now summon for help from nearby zones
  • Gas towers - are now live and will grow uncontrollably spilling out poison gas into districts
  • Huge Performance tweaks - Horde attacks and overall performance has improved based on feedback from the community

See Month 2 & 3 review in EA (Early Access)


See Month two review in EA (Early Access)


See Month one review in EA (Early Access)



About This Game

Cepheus Protocol is an open world real-time strategy (RTS) game where a mysterious virus of alien origin is sweeping through San Francisco. It is up to the Center for Epidemic Research and Control (CERC) to track down and find Patient Zero before it is forced to enact the cepheus protocol. Command your squad, defend your base, and stop the Pangu Virus before it is too late - how you do this is completely up to you.

The Pangu virus grows stronger by the minute. Destroy infection pods throughout the map to lower its spreading rate with the ultimate goal of hunting down and killing Chelsey to win. Be warned, each soldier under your command is equally at risk of becoming infected.

  • Take command of Captain Adrian Winter as she leads elite soldiers in an attempt to stop the Pangu Virus from spreading beyond containment.
  • Choose how to spend your in-game money on upgrading your barracks, buying better weapons, or acquiring new soldiers to fill your ranks. You earn in-game money by completing bounties and eliminating the infected.
  • Collect viral samples to better improve your squad’s abilities and expand your understanding of the virus before it is too late.
  • Every life matters and every soldier counts. If Captain Winter dies, it’s game over. Decide whether to leave her at the base or use her advanced skill-set to even the odds
    while in the field.
  • Use different squad formations to give you a tactical edge over the infected.
  • Utilize the specialized units and different team dynamics for maximum effect.

Note: Steam Remote Play is for allowing your friends to try out the game if you already have purchased it. Its not for a traditional coop this is planned in the current roadmap

System Requirements

    • Requires a 64-bit processor and operating system
    • OS: Windows 7/8/10 (64-bit)
    • Processor: Intel® Core™ i5-2500K / AMD FX-6300
    • Memory: 4 GB RAM
    • Graphics: NVIDIA GeForce 470 GTX or AMD Radeon 6870 HD series card or higher, 2GB VRAM
    • DirectX: Version 10
    • Storage: 6 GB available space
    • Sound Card: Direct X Compatible
    • Additional Notes: **recommended SSD install for optimal performance
    • Requires a 64-bit processor and operating system
    • OS: Windows 10 (64-bit)
    • Processor: Intel® Core™ i7-4770K / AMD Ryzen 5 1500X
    • Memory: 6 GB RAM
    • Graphics: NVIDIA GeForce 960 GTX or AMD R9280x card or higher, 6GB VRAM
    • DirectX: Version 11
    • Storage: 6 GB available space
    • Sound Card: Direct X Compatible
    • Additional Notes: **recommended SSD install for optimal performance

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