Meet possibly the best and worst way to play DOOM.
It's a remake of DOOM in Unity, called 1337d00m. Dario Zubovic, who has released it for free on itch.io, calls it a "hacker's version of the original DOOM".
"It's a parody of difficulty sliders in games," Zubovic said over email, although the mod's also a love letter to ASCII art. And the ASCII is the difficulty - the harder the difficulty, the larger each individual piece of text. Here's "impossible" difficulty:
The soundtrack is from Sydney band Turtle Skull — their debut album, in fact — which isn't bad for a self-imposed gamejam project. And being in Unity, you've got mouselook support off the bat as well. If you want to check Zubovic's creation out, head to itch.io. There's Linux and OSX versions, too.
Update: Amended mention of Turtle Skull's music: the soundtrack is from their debut album rather than anything exclusive for 1337d00m itself.