Loot boxes have come on strong over the past year or so, and so has resistance against them. But what if loot boxes had gained prominence 25 years ago? What if the id Software guys, instead of embracing shareware, had embraced RNG microtransactions? You'd very likely have ended up with something close to the Doom Loot Box Mod, created by ZDoom user Rip and Tear, which brings the old-time FPS you love into the modern era, in the worst way possible.
The Loot Box Mod removes weapons and powerups from the game, replacing some of them with UAC crates. Naturally, those crates are locked. Enemies have a "small chance" of dropping a key when they're killed, which you can collect and use as you see fit. But since there's absolutely no way to know what's inside the crates, you may as well just open 'em when you got 'em.
As you can see in the video below, resources have been dramatically reduced, loot boxes aren't super-common, and the items that pop out of them tends to be of the low-value variety: Shotguns are plentiful (although StronkiTonki got a bad break with those night vision goggles in his first crate), but plasma rifles? Not so much.
"Loot boxes in Doom, ladies and gentlemen! Have fun," he says at the end of his torturous adventure. "I'm sure I will probably never, ever use this again."
The mod also adds an in-game store selling both keys and crates—buy bundles of ten for the best value!—but alas, the store servers are offline.