This Steam Deck guide walks through installing Soulframe Open Preludes with the official launcher and Proton Experimental. I use a non-Steam shortcut, then return to Gaming Mode to sign in and play. The same installation process works on a Steam Machine running SteamOS; there is no invite code to hunt down first.
Open Preludes is open, but this is not a Steam release
Digital Extremes opened Preludes on 6 November 2026. Anyone wanting to try the PC build can create an account, download the launcher and start. This is a free playtest, not a requirement to buy a Founders bundle. An account is still needed for the download and the in-game login.
There are two important limits. The official FAQ describes Preludes as an evolving pre-alpha and says it is currently available through the Soulframe website rather than Steam or Epic. The download page also explicitly says there is no current Linux support. My SteamOS method therefore uses the Windows installer through Proton; it is not a native Linux release or a claim of official Steam Deck verification. Allow for the listed 50 GB of available storage and a broadband connection.
Steam Deck guide: download and add the installer
Start in Desktop Mode. On the Deck, press the Steam button, open the Power menu and select Switch to Desktop. Open your browser, visit soulframe.com and choose Play Open Preludes. Create a Soulframe account if needed, then log in. Select Play Free Now followed by Download Soulframe. The MSI installer is saved in Downloads.
Open Steam in Desktop Mode and go to Library. At the bottom left, choose Add a Game, then Add a Non-Steam Game and Browse. Open Downloads and change the file-type selector to All Files if the installer is hidden. Select the Soulframe MSI, click Open, then Add Selected Programs.
Find the new library entry, open its gear menu and choose Properties. I rename the shortcut to Soulframe, removing the MSI suffix. Open Compatibility and choose Proton Experimental as the compatibility tool. Close Properties and press Play to run the installer. This Steam Deck guide uses that direct route; our NonSteamLaunchers guide covers a separate launcher-management approach, which is not required here.
Choose the folder and finish downloading
The installer asks where to put the game. I chose a Soulframe folder I had already created inside my Games folder. The installer’s Z drive exposes the normal Linux folders. If you want a custom location, create that folder beforehand. Alternatively, keep the default C-drive location, which stays within this shortcut’s installation environment. You do not need to copy my folder choice to follow the rest of the process.
There is a cleanup difference worth remembering: if you choose your own folder and later remove the Steam shortcut, that folder needs to be deleted manually when you want to reclaim its space. Removing the shortcut alone is not the same as removing those game files.
Let the launcher download the game. When it asks whether to optimise the installation, I choose Yes. This takes a little time, so let it finish before continuing. Once it is done, press Enter. The game should open to its login screen; at this stage I use that only as a launch check, rather than signing in from the desktop.
Return to Gaming Mode and sign in
At the login screen, choose Exit and confirm Yes. I then use the desktop application launcher to restart the Deck, which returns it to Gaming Mode. Soulframe appears among the recent games. Open it, press Play and sign in with the Soulframe account details used on the website.
Custom library artwork is optional. I use Decky Loader with the SteamGridDB plugin: open the game’s options, choose Change Artwork and select the images you want. Neither plugin is needed to install the game or reach the login screen. If you already use Decky, our Decky Direct Updater guide covers a separate way to keep plugins updated, rather than an extra Soulframe installation step.
My starting settings on Steam Deck
After entering the world, dismiss the patch notes and open Settings. I start with Borderless Fullscreen at 1280 x 800, vertical sync off and the maximum frame-rate setting at 60. Upscaling is FSR 3 on Quality. Under Graphics, I select the Low preset and disable the advanced effects, then raise Geometry Quality and Texture Memory to Medium.
These are starting settings for the handheld, not a measured performance target. Setting the maximum frame rate to 60 does not establish that the game runs at 60fps. I am not presenting these choices as a tested Steam Machine preset either: the shared part of this Steam Deck guide is the SteamOS installation process, not an assumption that different hardware needs identical graphics settings.
Choose Exit when you finish
To quit, open the menu and choose to leave the game. On the next prompt, select Exit rather than Log Out. Exit is the quit option that returns to SteamOS. When I launch again, the email address is remembered, but I still need to enter the password each time.
That leaves the process straightforward: download the official installer in Desktop Mode, add it as a non-Steam game with Proton Experimental, finish the installation and play from Gaming Mode. Open access removes the invitation wait, but Preludes is still changing. I would treat this Steam Deck guide as an installation starting point for the current build, rather than a promise that every future update will behave identically.
