OLD CLASSICS (1993-2003):
The first 10 years of Doom Modding were an interesting bunch. Back then, while there was interest, it was pretty hard to make maps back in this era - this is before Boom-compatible mapping became popular. Many old mapsets from this era are worth mentioning, however. All of the collections here are known as "Megawads", generally 32 maps (same as Doom 2). There's plenty of notable single map releases from this era, but you'll have to hunt those down - there are a lot of them scattered about.
DOOM and DOOM II
You may argue that DOOM and DOOM II aren't mods. You're right, but they are still by definition the most classic mapsets ever made.
Authors: John Romero, Sandy Petersen et al.
Release Years: 1993 and 1994
Number of maps: Ultimate DOOM: 36, DOOM II: 32
The Plutonia Experiment and TNT: Evilution
Final Doom (or Final DOOM as a brand) is a pair of standalone Doom II modifications, TNT: Evilution and The Plutonia Experiment, which include full sets of new levels, some new graphics and textures and some new music in the former case, in addition to most of the resources from Doom and Doom II. It was published on June 17, 1996 by id Software under the initiative of John Romero and developed by members of the fan community belonging to TeamTNT.
TNT: Evilution was developed independently by TeamTNT, and was purchased by id Software when it was practically complete. The Plutonia Experiment, on the other hand, was completed specifically for Final Doom after its authors showed some of the id Software developers an incomplete set of levels. Its two authors, while part of TeamTNT and also contributors to Evilution, produced Plutonia independently. The Plutonia Experiment is significantly harder than TNT: Evilution.
Authors: Dario and Milo Casali (Plutonia) and TeamTNT (TNT)
Release Year: 1996
Number of maps: Plutonia: 32, TNT: 32
Memento Mori and Memento Mori II
Memento Mori is a 1995 megawad that contains 32 new levels, designed by two members of the Innocent Crew, Denis and Thomas Möller, along with 19 other authors, including Tom Mustaine and both Dario and Milo Casali. It was initially released on December 10, 1995, and saw an updated release in February 1996. In contrast to most megawads, it is designed especially for cooperative multiplayer gameplay, although it can be played in single-player as well.
Memento Mori II (MM2.WAD) is a 1996 megawad that contains 32 new levels, plus two top-secret levels that are not contained in the WAD file itself (see Accessing the top-secret levels). Released on July 27, 1996, it is the sequel to the 1995 megawad Memento Mori, with many of the same designers involved, including Denis and Thomas Möller of the Innocent Crew. Like its predecessor, and in contrast to most megawads, it is designed especially for cooperative multiplayer gameplay, although it can be played in single-player as well.
Authors: Collaboration of 21 different authors
Release Years: 1995 and 1996
Number of maps: Memento Mori: 32, Memento Mori II: 32
Download MM1 Download MM2
Icarus: Alien Vanguard
Icarus: Alien Vanguard (ICARUS.WAD) is a 32-level megawad released in 1996 by TeamTNT. It was developed as the collective's first freeware release, after TNT: Evilution was picked up for publishing by id Software for what would become Final Doom. The first level sees the player commandeering a shuttle and flying it to the infested exploration cruiser, the Icarus. From there, the player must fight through the ship, regions of the neighboring planet, and unsafe simulations to cleanse the demonic threat. A sequel, Daedalus: Alien Defense, was released in 2003 - that one is a ZDoom map pack.
Author: TeamTNT
Release Year: 1996
Number of maps: 32
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Requiem
Requiem (REQUIEM.WAD) is a 1997 megawad that contains 32 new levels, uploaded to the idgames archive on July 4, 1997. Several of its designers previously worked on Memento Mori and Memento Mori II. It is famous for popularizing architectural tricks that are used even today, including fake 3D bridges.
Authors: Various
Release Year: 1997
Number of maps: 32
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Hell Revealed
Hell Revealed (HR.WAD) is a 32-level megawad for Doom II, released on May 2, 1997. It was created by speedrunner Yonatan Donner and his friend Haggay Niv. This megawad was designed with full skill level support to allow unskilled players to complete it, and yet also provide "extreme challenge" for the best players. The latter is the best-known feature of Hell Revealed.
While all 32 of Hell Revealed's maps run in Vanilla, if you want to save in MAP24, you must use a Limit-Removing source port.
Authors: Yonatan Donner and Haggay Niv
Release Year: 1997
Number of maps: 32
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Alien Vendetta
Alien Vendetta (av.wad) is a 2001 megawad that contains 32 new and hard levels.
There have been two separate releases of Alien Vendetta. The second release, made in 2002 when it was selected for usage on Compet-n, made various changes to almost all of the levels; the biggest change is the replacement of MAP25: Valley of Echoes with another map, MAP24: Clandestine Complex, as well as the relocation of the former MAP24: Demonic Hordes to MAP25.
On August 1, 2016, the expansion Alien Vendetta: Black Label (avbl_v1.wad) was released on the megawad's website, coinciding with a revamp of the site's design. The wad features two new levels that replace MAP01 and MAP02, designed to then-modern level design standards by Brad Spencer (Vorpal). It must be loaded alongside Alien Vendetta to play. On September 27, 2016, the original 2001 version was re-released on the website as well.
Like with Hell Revealed, a Limit-Removing source port is required to save on many of the later maps in this wad.
Authors: Various
Release Year: 2001, then 2002
Number of maps: 32
Find it here
Scythe
Scythe is a 32-level megawad released by Erik Alm in April of 2003. The most distinguishing feature of Scythe is that most of its levels are smaller than average. Also, it was created in a matter of a few months.
Authors: Erik Alm and Kim "Torn" Bach
Release Year: 2003
Number of maps: 32
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NEO-RETRO (2004 and onwards):
Interest in Vanilla Mapping is less than what it used to be, owing to the popularity of Boom and ZDoom, but that doesn't mean there isn't the occasional bone throne. If restriction breed creativity, then these mappers have completely exploded with said creativity.
Hell Revealed 2
Hell Revealed II (HR2) is a 32-level megawad for Doom II and the sequel to the legendary Hell Revealed. The WAD was authored by a team of 14 members led by Jonas Feragen. It was released in December of 2003. Many have admired this megawad for being quite possibly one of the most difficult wads to date.
Hell Revealed II had a long gestation, with development beginning in 1998. On February 14th 2000 a "beta" version of the megawad was released with 15 levels, and two secret levels. A number of demos were recorded on this version. The intention was to release the full megawad that year, but several years passed before Andy Olivera pulled the project together and released the final version. It requires a Limit-Removing source port to save on many maps, but it will run in Vanilla Doom.
Authors: 14 authors lead by Jonas Feragen
Release Year: 2003, effectively 2004
Number of maps: 32
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Scythe II
Scythe 2 is a 32-level megawad for Doom II, released by Erik Alm in June of 2005. It was re-released July 10th 2009 with the three missing levels. It has been regarded by many as a spiritual successor to Scythe rather than a direct sequel. While the original featured small, action-packed levels, Scythe 2 is filled with large, complex and detailed maps, and is sometimes compared to the style of Alien Vendetta.
Scythe 2 is split into six episodes, and upon finishing one the player loses all his weapons and ammo and is forced to start the next episode with a pistol and fist. Each contains a different style and setting.
Notable for using DEHACKED to create two custom monsters. It requires a Limit-Removing source port to play.
Authors: Erik Alm
Release Year: 2005, then 2009
Number of maps: 32
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Doom The Way id Did / Doom 2 The Way id Did
Doom the Way id Did (DTWiD for short) is a 2011 megawad for Doom containing 27 new levels designed to mimic the mapping style of Sandy Petersen, John Romero and Tom Hall. The project was founded by Hellbent as a community project and later led by a core group consisting of Ellmo, Esselfortium, Xaser, Marnetmar, and Alfonzo who oversaw the map selection and finalization process. The project also features artwork by Kracov and an optional soundtrack by Mr. Freeze. It also runs on the original Vanilla Doom.exe, in case you have a time machine.
Doom 2 the Way id Did (D2TWiD for short) is a 2013 megawad for Doom II containing 32 new levels designed to mimic the mapping style of Sandy Petersen, John Romero and American McGee (plus a 33rd level as an Easter egg spoofing Betray). The project was a continuation of Doom the Way id Did. Instead of being themed after Wolfenstein 3D, the two secret levels are themed after Commander Keen.
Authors: Various
Release Years: 2011 and 2013
Number of maps: DTWiD: 27, D2TWiD: 32
Find DTWiD Find D2TWiD
Interception
Interception is a vanilla-compatible 32-level megawad for Doom II released in 2013. Work began on creating a megawad following the rejection of maps by Matt534Dog submitted to Doom the Way id Did (which later became E4M7 and E6M4 of Doom the Way id Did: The Lost Episodes). He was soon joined by numerous mappers, including Callum Guy Oliver (phobosdeimos1), who passed away before the WAD was released. Interception also features a completely new soundtrack, composed by XenoNemesis and Stuart Rynn (stewboy).
Author: Matt534Dog et al.
Release Year: 2013
Number of maps: 32
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No End in Sight
No End In Sight is a megawad for The Ultimate Doom created by three Doom the Way id Did contributors: Emil Brundage (NaturalTvventy), Xaser Acheron, and Christopher Lutz. The megawad includes both new levels and levels modified from Doom the Way id Did. The first three episodes are vanilla-compatible, whilst the fourth episode requires a limit-removing source port.
Authors: Emil Brundage et al.
Release Year: 2016
Number of maps: 36
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Back To Saturn X
Back to Saturn X is a series of megawad/partial conversion projects for Doom II, designed to be compatible with DOOM2.EXE. It features an exclusive texture set, original music, and a new palette and colormap.
Song and album titles from Guided by Voices provide the title, episode names, and map names. Titles and song lyrics are incorporated into the text screens as well.
The first episode was originally released on December 10, 2012 for Doom's 19th birthday, featuring twenty regular levels, one secret level, and a recurring train station hub. An additional level was inserted in a later release on August 1, 2013. The first non-beta release was on February 27, 2017, and inserted another additional level. The episode received one of the 2013 Cacowards.
The second episode was released on 1 September, 2014, with another twenty-two levels, a secret level, four episode hubs and an ending screen. It received one of the 2014 Cacowards.
One final episode remains in development as of this writing.
Authors: Various
Release Year: Multiple releases between 2012 to 2017
Number of maps: Episode 1: 27, Episode 2: 27
Episode 1 Episode 2
Doom 4 Vanilla
Also Known As: Doom 2016 the Way 1993 Did It.
Doom 4 Vanilla (D4V) is a gameplay mod for Vanilla Doom that attempts to re-create many of the features of DOOM 2016 (also called Doom 4 by many fans) inside of the confines of Doom2.exe.
D4V is 100% vanilla compatible and full of dehacked tricks. All under the limitations of the original Doom2.exe. Works on any source port. Also works without a source port, if you have a time machine.
Noiser is an absolute mad lad.
Author: Noiser
Release Year: 2019
Gameplay Mod
Find it here