The Proton update adds 18 more Windows games that run on Linux, including Chex Quest HD.

In order to play Windows-compatible games on its Linux-based operating system, Steam Deck uses a compatibility layer called Proton. It’s a suite of different technologies, including the venerable Wine software and software that translates Windows-native Direct3D API calls into Vulkan API calls that Linux can handle.

Proton is constantly updated to fix rendering bugs in certain games and add new games to the compatibility list; Version 8.0 was released yesterday and adds support for a total of 18 new games (and fixes rendering bugs in a lot of others). Pierre-Loup Griffet of Valve called the release “our biggest rebase to date”.

The new compatibility list includes several big, recognizable games that you’d expect Valve to prioritize, including the 2023 re-release of Dead Space and Square Enix’s Forspoken. But there’s one odd game that stands out to me: Chex Quest HD, a remastered version of the game on CD that was free in boxes of Chex cereal for six weeks in the mid-90s.

The original Chex Quest was a remastered and modified version of The Ultimate Doom, a re-release of the 1993 original in 1995. For PC gamers of the time who had already switched to Quake, its old graphics and gameplay (as well as its frankly uncool corporate branding and childish aesthetic) made it look dated. But for kids with no steady income and/or parents who didn’t want them to play something as violent as Doom, it served as an introduction to the first-person shooter genre.

Its strangely loyal fan base has given the Chex Quest franchise a much longer shelf life than a typical box of cereal. Free sequels followed in 1997 and 2008, and the 2008 release of Chex Quest 3 also included updated ZDoom versions of the first two games with other modifications and bug fixes. Chex Quest HD, a game supported by the Proton 8.0 release, is a complete remaster of the original built using Unreal Engine 4. It is a free download for Steam users, and a $5 Nintendo Switch version is also available.

While the new Proton updates primarily benefit Steam Deck, it is an open source tool and Valve includes it with all versions of Steam for Linux. Find and enable the Steam Play option (Canonical has Ubuntu instructions here, but should be the same on most distributions) and you should be able to try officially supported and tested Windows games on your Linux PC. There is also an experimental branch if you want to try a game that is not on the official support list.

Proton 8.0 update requires Vulkan 1.3 capable GPU. While this version of the Vulkan specification was only finalized in early 2022, all GPUs that are still receiving driver updates from their manufacturers should support it. The Khronos Group Compliance List shows Vulkan 1.3 support for integrated Intel GPUs starting with 2017 7th Gen Core processors and all Iris Xe and Arc GPUs; AMD GPUs as old as the 2016 Radeon RX 480; and Nvidia GPUs as old as the 2014 GeForce GTX 750 Ti.