Steam + FOSS-alternative programs for Linux gamers

Linux Mint is one of the most popular desktop Linux distributions and used by millions of people. The purpose of Linux Mint is to produce a modern, elegant and comfortable operating system which is both powerful and easy to use. Latest: Uma (20.2).

Steam is a digital distribution, digital rights management, multiplayer and communications platform developed by Valve Corporation.

Games library manager.
Supports: Steam, GOG, Humble Bundle, Humble Trove, Wine and RetroArch
.

An online game marketplace and community. Also an app which manages downloading and updating of games acquired through the website.

Lutris is an open source gaming platform for GNU/Linux. It allows you to gather and manage (install, configure and launch) all your games acquired from any source, in a single interface.

Run Windows software on Linux and other supported systems in an advanced Windows runtime rather than emulation.

Proton is a tool for use with the Steam client which allows games which are exclusive to Windows to run on Linux kernel and macOS operating systems. It uses Wine to facilitate this.

Most users will prefer to use Proton provided by the Steam client itself. The source code is provided to enable advanced users the ability to alter Proton. For example, some users may wish to use a different version of Wine with a particular title.

Getting Started with Proton from Steam Play
Make sure you are opted into the Steam Client Beta!
Proton requires graphics drivers that are more recent than what is typically packaged in most distributions; please read the list of requirements and quickstart for Ubuntu 18.04 users: https://github.com/ValveSoftware/Proton/blob/proton_3.7/PREREQS.md
Install and play games! Please refer to this post for more information: https://steamcommunity.com/games/221410/announcements/detail/1696055855739350561

Proton has DXVK which can be used as primitive HUD:
https://github.com/doitsujin/dxvk#hud

A Vulkan-based translation layer for D3D9, D3D10 and D3D11, which can be used on Linux with Wine.

Currently unsupported features:
D3D11: Shared Resources.
D3D11: Class linkage.
D3D11: Predication.
D3D11.1: Target-independent rasterization (behaves incorrectly; no MSAA16x support).
D3D11.2: Tiled resources (optional).
D3D11.3: Rasterizer Ordered Views (optional).
D3D11.4: D3D12 interop.

https://github.com/doitsujin/dxvk/wiki

Notes on Vulkan drivers
Before reporting an issue, please check the Wiki page on the current driver status and make sure you run a recent enough driver version for your hardware.

DXVK can be used to monitor performance with DXVK_HUD:
https://github.com/doitsujin/dxvk#hud

vkBasalt is a Vulkan post processing layer to enhance the visual graphics of games.

Currently, the build in effects are:

Contrast Adaptive Sharpening
Denoised Luma Sharpening
Fast Approximate Anti-Aliasing
Enhanced Subpixel Morphological Anti-Aliasing
3D color LookUp Table

It is also possible to use Reshade Fx shaders.

CoreCtrl is a Free and Open Source GNU/Linux application that allows you to control with ease your computer hardware using application profiles.

Linux (GTK3+) GUI to view detailed information about and configure AMD GPUs settings.

Open source RGB lighting control that doesn't depend on manufacturer software.

Collects and logs details about game performance in games using OpenGL/Vulkan. Can display live statistics in overlay.