Nuts by B.R.P.D. (Doom II mod)

From doomwiki.org:

Nuts is a single-level PWAD for Doom II meant for limit removing source ports. It was designed by Bernard De Windt (B.P.R.D) and uses as its music track a MIDI sequence of "Kashmir" by Led Zeppelin.

Nuts is a massive slaughter map featuring a deliberately outrageous number of enemies, known for slowing down even the most powerful of computers to a crawl upon release. It was created to test the /idgames archive upload function for the author's contemporary work, Equinox, and is now remembered as a quintessential joke WAD. Two years later, it received two sequels, Nuts 2 and Nuts 3.

Nuts has become an extremely well known map in the community. In 2003, it was added to the Top 10 Infamous WADs, and in 2018 was featured in Doomworld's Top 100 Most Memorable Maps, placing fourth. It continues to elicit interest among YouTube channels dedicated to Doom and speedrunners.