What are some alternatives?
When comparing Metro Exodus and Doom, you can also consider the following products
Duke Nukem Forever - Duke Nukem Forever is an Action-Adventure, First-person Shooter, Single and Multiplayer video game developed by 3D Realms and published by 2K Games.
Quake - Quake is a series of first-person shooter video games released by id Software.
Team Fortress 2 - Team Fortress 2 (TF2) is the sequel to the game that put class-based, multiplayer team warfare on...
Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
Warface - Warface - is a free online shooter with diverse PVP modes, exciting PVE missions, outstanding arsenal and millions of fans around the world!
Call of Duty - Call of Duty is a first-person and third-person shooter series by Infinity Ward.