Cepheus Protocol

Is Cepheus Protocol still being updated?

The last update to Cepheus Protocol was posted 2 months ago, on Sep 4, 2026. That is longer than a month, but within the last three. Over the past year updates to Cepheus Protocol have come about every 6 days.

1. Sep 4, 2026Update2026.9.4 Experimental Patch Notes & September Development Update
2. Aug 21, 2026Update2026.8.21.1 Experimental Patch Notes & August Development Update
3. Aug 13, 2026Update2026.8.13.1 Now Out: Final Push to Escalation
4. Aug 5, 2026Update2026.8.4.1 + 4.2 Experimental and Normal Patch Notes
5. Aug 1, 2026Major update2026.7.31.3 Quality of Life Update Live + GPU Fog of War Tonight on Experimental
6. Jul 28, 2026Update2026.7.27 CERC OPS Arrives on Experimental Plus Major Fixes
7. Jul 12, 2026Update2026.7.11 AI, Performance & Helicopter Systems Update on Experimental
8. Jun 20, 2026Update2026.6.19.5 Discord Integration Fixes + Launcher
9. Jun 19, 2026Update2026.6.18.2 Weather System, Discord, Vehicles, and Pandemic Fixes
10. Jun 11, 2026Update2026.6.11.1 QOL Improvements and Bug Fixes

31 earlier updates and other posts

1. Jun 8, 2026Major update2026.6.8.2 Civilian Evacuation Live On Public
2. Jun 3, 2026Update2026.6.2.1 : Now out!
3. May 31, 2026Patch2026.5.30.6.2 : Hotfix
4. May 31, 2026Update2026.5.30.6: Evacuation Waystations and Efficiency Controls
5. May 24, 2026Update2026.5.24.1 & The Next 60 Days of Cepheus Protocol
6. May 23, 2026Major update2026.5.22.9 Experimental Civilian Evacuation Preview, SF North Live
7. Mar 7, 2026Update2026.3.7 Vehicle Pathing Improvements & Helicopter tweaks
8. Mar 6, 2026Update2026.3.6.1 Revised Power Balance and Bug Fixes
9. Feb 27, 2026Update2026.2.28.2 Live on Experimental, March is Civilian Evac Month
10. Feb 20, 2026Update2026.2.20.1 – Difficulty and Pacing Controls Now Live
11. Feb 13, 2026Update2025.2.13.1 – Pandemic Save UI Live + Pathfinding AMA Tonight
12. Feb 12, 2026Update2025.2.12.1 Pandemic Save UI Live on Experimental + Pathfinding Sit-Down
13. Feb 7, 2026Update2025.2.7 Update: Pandemic Saves, Rehostable Co-op, Rebuild Proof
14. Jan 31, 2026Major update2026.01.30.3 Doctrines Have Arrived (Shared Progression Is Now Live)
15. Jan 17, 2026UpdateDoctrine Preview on Experimental This Weekend (Dev Report Friday)
16. Jan 11, 2026PatchPatch Notes 2026.01.10.1
17. Jan 10, 2026UpdatePatch Notes 2026.01.10
18. Jan 10, 2026UpdateFirst 48 Hours After the Rebuild Merge | Patch Notes 2026.1.9.2
19. Jan 7, 2026Major updateThe Rebuild Is Now the Main Game (Build Switch Update)
20. Nov 24, 2025UpdatePatch Notes 2025.11.23.2 - public-playtest - Custom Game options now in!
21. Nov 7, 2025UpdatePatch Notes 2025.11.7 - public-playtest Treasure Island Now playable!
22. Oct 31, 2025UpdatePatch Notes 2025.10.30.3 - public-playtest Treasure Island Now playable!
23. Oct 23, 2025UpdatePatch Notes 2025.10.23.2 - public-playtest
24. Oct 17, 2025UpdatePatch Notes 2025.10.17.2 - public-playtest
25. Oct 15, 2025PatchPatch Notes 1.3.4.16 Legacy
26. Oct 14, 2025UpdateThe Battle of Half Moon Bay | Patch Notes 2025.10.13.6 - public-playtest
27. Oct 12, 2025UpdatePatch Notes 2025.10.11.1 - public-playtest
28. Oct 11, 2025UpdatePatch Notes 2025.10.10.1 - public-playtest
29. Oct 10, 2025PatchPatch Notes 2025.10.9 - public-playtest
30. Oct 9, 2025UpdatePatch Notes 2025.09.5.3 - public-playtest
31. Jul 24, 2026NewsWorld Reveal of CERC Ops This Saturday!
32. Jul 20, 2026NewsMassive Performance Gains and Smarter Fog of War Are Coming
33. Apr 11, 2026NewsCivilian Evacuation Changes Everything
34. Mar 27, 2026NewsPhase 3 is fully underway, and the end is in sight
35. Mar 14, 2026AnnouncementCERC HQ Stream Tonight | Phase 2 Wrap Up and Civilian Evacuation 2.0
36. Dec 15, 2025NewsDevelopment Update – Vehicles, Systems Progress, and What’s Coming Next
37. Nov 7, 2025NewsThe Battle of Half Moon Bay
38. Sep 24, 2025NewsPandemic & Helicopter Preview Live

How long has Cepheus Protocol been in early access?

Cepheus Protocol entered Early Access on Steam on May 15, 2020 and has been in it for 6 years, 6 months.

How many people are playing Cepheus Protocol?

Cepheus Protocol peaked at 87 players on Steam in the last 24 hours.

What is Cepheus Protocol?

Steam users tag Cepheus Protocol as Sandbox, Zombies, RTS, Survival and Post-apocalyptic. Cepheus Protocol is online co-op and priced at $19.99, and 76% of its 3,038 Steam reviews are positive.

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.

Browse related lists

Co-op early access gamesOnline co-op early access gamesMultiplayer early access gamesEarly access games under $20Early access games for Steam DeckEarly access survival gamesEarly access strategy gamesEarly access open-world gamesEarly access sandbox gamesEarly access zombie games

Steam tags: Sandbox, Zombies, RTS, Survival, Post-apocalyptic, Building, Strategy, Gore, Open World, Singleplayer.

Status	Slowing
Early access since	May 15, 2020
Last update	Sep 4, 2026
Typical gap	6 days between updates
Playing now	87 (Nov 14, 23:48 UTC)
7-day peak	87
Steam reviews	76% positive of 3,038
Price	$19.99
Play	Online co-op
Steam Deck	Playable
Platforms	Windows
Developer	Halcyon Winds
Publisher	Halcyon Winds

All news on Steam Discussions Guides