How to play StarCraft 2 Coop missions alone
StarCraft 2 is a well-known Real-Time Strategy (RTS) game. It features campaigns, skirmishes (alone or with other players), PVP matches and Coop missions. These are missions that have to be played with a selected Coop Commander. A unit representing a distinguished play-style, also gaining more abilities and/or useable units as the Commanders levels up.
The problem
The problem? Coop missions can ONLY be played in multiplayer with another player. And lately I wanted to play a few coop missions but found no other players. The player queue was completely empty. Given that StarCraft 2 was released in July 2010 this isn't surprising, as the coop part was never StarCrafts most beloved part. Yet Blizzard offered Coop Commanders for money, which players could buy. And I bought one (my beloved Mengsk) and not being able to play with something I bought didn't sit well with me.
I googled if there was any way to play StarCraft 2 coop missions alone. The solution which came instantly to my mind was: Install StarCraft 2 on my laptop, create 2nd Battle.Net account, and use that to join up, start the mission and just leave. However.. This seemed somewhat laborious. There has to be a way not involving a second PC, right?
Turns out, there is!
The solution
All we need is the program ProcessExplorer from SysInternals. And a second Battle.Net account - as StarCraft 2 as all Blizzard games nowadays has a strict online requirement.
Once we have that, it's merely the process of clicking a few buttons in ProcessExplorer. This will allows us to run a second instance of StarCraft 2 on my gaming PC. In this instance I log in with my second account, team up with my main account and can happily start a coop game. Once started I just leave the game with one account and be done.
Credits where credits are due
The crucial information was found in this Reddit-Thread: r/starcraft2coop: What's the current best way to get into a solo co-op game?
Despite being 5 years old, it's information is still accurate in June 2026. Reddit user u/braindoper gave detailed instructions in his comment.
Either the arcade maps, or if you want to use the actual mode: Party up with someone that leaves/stays afk. This can be yourself on a second account, even on the same computer!
To run SC2 twice on the same computer, you either need to sandbox the game (google how to, but this requires a download since Windows doesn't come with the essential tools to control what programs do on your computer), or you need to close a few handles the SC2 process opens after opening the first one. With these handles closed SC2 doesn't noticed if it's running already. They are:
\BaseNamedObjects\StarCraft II Game Application (Global)
\Sessions\1\BaseNamedObjects\StarCraft II Game Application
\Sessions\1\BaseNamedObjects\StarCraft II IPC Mem
\Sessions\1\BaseNamedObjects\StarCraft IIGoogle how to do this. It doesn't require downloads, and can also be automated. After any of these steps, you can open a second SC2 process, log in into a free second account and team up with yourself.
I play 95% of my games this way. It's way more relaxing for me. Playing with someone else puts pressure on me.
And due to some other Redditor asking how to do that, braindoper even gave a link to a YouTube-Video showing detailed instructions. Yai!
For fun! And... fun!
And yes, the steps shown in the video work. Additionally I noticed a comment under the YouTube-video which recommends using the SC2Switcher_x64.exe found under Drive:\StarCraft II\Support64\ which allows easier switching of Battle.Net accounts.
Just played my first mission, no problems. Yai! If your PC isn't good enough to keep two StarCraft 2 games running at the same time, just close the second one after the missions starts.
