Is Combined Arms Operations Series co-op?

Yes, Combined Arms Operations Series supports co-op.

Does Combined Arms Operations Series have PvP?

Yes, Combined Arms Operations Series has player-versus-player modes.

Do we both need to own Combined Arms Operations Series to play together?

Yes. Combined Arms Operations Series is played online, so each player needs their own copy on their own Steam account (or PC Game Pass where it is offered). Steam Families can share a library, but two people cannot play the same shared game at the same time.

How many people play Combined Arms Operations Series?

Player counts were not available when this page was built.

Ready Up — what game do we play?Compare two Steam libraries →

Multiplayer games › Strategy › Turn-based & grand strategy

Is Combined Arms Operations Series multiplayer or co-op?

Yes — co-op and PvP. Combined Arms Operations Series is a turn-based & grand strategy game released in 2021, 90% positive on Steam (21 reviews). $19.99 on Steam.

Co-opPvPSingle-player tooStrategy · Turn-based & grand strategy

The Combined Arms Operations Series simulates hypothetical battles between World War II armies. Assemble your…

How Combined Arms Operations Series plays with friends, according to Steam

Online co-op: Yes
Local / split-screen co-op: Not listed on Steam
Online PvP: Yes
LAN play: Not listed on Steam
Single-player mode: Yes
Mods: Steam Workshop

Steam's own category list for the game, as of 2026-09-09. "Not listed" means the store page does not claim that mode; community mods or Remote Play can still add it.

Steam tags: Simulation, Strategy, Turn-Based Strategy, World War II, Wargame, War, Historical, Alternate History

Do you and a friend both own Combined Arms Operations Series?

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

Or open the Steam store page.

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Tired of Combined Arms Operations Series? The Swap tab finds the closest unowned games of the same type that are newer or rated higher.

Quick answers

Is Combined Arms Operations Series co-op?: Yes, Combined Arms Operations Series supports co-op.
Does Combined Arms Operations Series have PvP?: Yes, Combined Arms Operations Series has player-versus-player modes.
Do we both need to own Combined Arms Operations Series to play together?: Yes. Combined Arms Operations Series is played online, so each player needs their own copy on their own Steam account (or PC Game Pass where it is offered). Steam Families can share a library, but two people cannot play the same shared game at the same time.
How many people play Combined Arms Operations Series?: Player counts were not available when this page was built.

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; page updated 2026-09-23. Powered by Steam — not affiliated with or endorsed by Valve Corporation or Microsoft. Ready Up is a Somebody Decide program. How the data works · Legal & privacy · All types · Game Pass