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Multiplayer games › Survival › Zombie survival

Is Cepheus Protocol multiplayer or co-op?

Yes — co-op, plus local/split-screen. Cepheus Protocol is a zombie survival game released in 2020, 79% positive on Steam (3,032 reviews), with 20 playing right now. $19.99 on Steam.

Co-opLocal / split-screenSingle-player tooSurvival · Zombie survival

Cepheus Protocol is an Open World RTS Military Survival Game. Play as the CERC hunting Patient 0, maintain Quarantine camps, fight dangerous mutations & Rogue…

Steam tags: Sandbox, Zombies, RTS, Survival, Post-apocalyptic, Building, Strategy, Gore

Do you and a friend both own Cepheus Protocol?

Ready Up compares two Steam libraries and shows every multiplayer game you both have — including whether Cepheus Protocol is one of them — then helps you pick tonight's game with a weighted roll or a bracket.

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Unturned
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SCUM
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State of Decay 2: Juggernaut Edition
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Tired of Cepheus Protocol? The Swap tab finds the closest unowned games of the same type that are newer or rated higher.

Quick answers

Is Cepheus Protocol co-op?
Yes, Cepheus Protocol supports co-op.
Does Cepheus Protocol have PvP?
Steam does not list PvP for Cepheus Protocol.
How many people play Cepheus Protocol?
About 20 players were in-game when this page was built (2026-09-09).

Ready Up is a free tool: enter two Steam usernames and it lists the multiplayer games you both own, runs a bracket to pick one, and suggests new co-op games that fit how you both play. Ratings, tags and player counts from Steam and SteamSpy; updated 2026-09-09. Powered by Steam — not affiliated with or endorsed by Valve Corporation.