Nuts was selected as one of Doomworld's Top 10 Infamous WADs, and it's not hard to see why. B.P.R.D. went on to have a long, distinguished career as a Doom author; his followup to this bit of totty was Equinox, of all things. It's hard to imagine someone not knowing or understanding what Nuts is, but I'll humor you. Released late in 2001, this is a single map replacement for Doom II. You won't be able to run this in vanilla; I recommend the PrBoom-Plus family for sheer efficiency, but I didn't have much trouble working it in ZDoom. Nuts does have a story, with you sent to eliminate the final Hellspawn army on Litrivin IV, armed with nothing but a pistol because of a past social transgression. Good thing there is a fuck ton of cell ammo and guns at the drop off point, I guess.
Anyway, Nuts is little more than two really big and simple outdoor areas. One is filled with almost every land-bound Doom II monster and the other is filled with arch-viles, Cyberdemons, and Spider Masterminds. There is no way that you will be able to kill everything, mostly due to the fact that the inevitable survivors will be a big mass of Cyberdemons in the second room. There is simply not enough ammo, with or without infighting. Not that there's a without. If Doom's enemies didn't hate each other almost as much as they hate you, this would be a fruitless endeavor. Thankfully, their free-floating hostility means that most of the population will quickly dispatch each other.
Nuts is a practical demonstration of the importance of infighting. Fire some BFG shots to get the imps out of you way depending on the direction you break and then just do a little bit of crowdshaping before whipping the whole horde into a circle of death. Eventually, you'll be left with the revenants and the barons, and after that, just the barons. The exercise almost falls apart in the second half, since there's no way to dispatch all of those Cybers, but a little bit of crowdshaping can form a weak point in the wall that you can hope to punch through. The skills are rudimentary, and the execution pretty boring after the first few minutes, but the fundamentals are there.
Really, NUTS is utterly lacking in guile. By B.P.R.D.'s own account, it was tossed off as an exercise in silliness, and its ongoing infamy shows - if nothing else - that the constantly changing Doom community is not as jaded as one might believe. I wouldn't recommend it for a play as it is much more of a historical curiosity these days, though I must admit that there is something captivating about watching the monsters die in droves during the opening moments.