Doom 3 (Original) Gameplay and Settings - Steam Deck
Settings at: 4:20
Game plays/runs great! Running through Dhewm3 downloaded through "Discover" on Desktop Mode. When you install Doom 3 it will create a folder called "base". When you first run Dhewm3 it will tell you where to put the "base" folder.
I definitely recommend playing original Doom 3 first and not the BFG edition. If the flashlight as a "weapon" that you have to switch to turns you off from the game, try to look at it more as a tool rather than something that should be on all the time.
The dark environments in this game are so well done and it just adds to the intensity when you don't have the flashlight out all the time and you start looking for environmental things to give away enemy positions.
*I had mouse smoothing up a good bit on this one, so if you notice the animations/arms not matching my turning speed exactly, that's probably why.
Steam OS
Dhewm3