Simplicity

Simplicity is a 21-level megawad created for ZDoom by Melissa McGee (Agent Spork), split between two episodes. The mod features a series of fairly short maps, a part of which are speedmaps, and utilizes a lot of ZDoom features, but despite this it strongly adheres to vanilla gameplay, aiming to offer a fast-paced and simple experience as opposed to more elaborate total conversions (and hence the name). It was originally released on the 25th of October 2005.

Two years later, on the 7th of September 2007, an updated version of the megawad called Ultimate Simplicity was released, which among other things improved some of the already existing maps, replaced some of them entirely and offloaded the scrapped maps into a third episode called the Director's Cut.

Simplicity received one of the 12th Annual Cacowards.

Custom monsters
Several new enemies are included through the DECORATE lump:
 * Nightmare demon:A dark-skinned variant of the demon that becomes semi-translucent upon spotting the player, akin to the spectre in Doom 64. It can also shoot green projectiles, briefly revealing itself. It has 260 hit points (thing type 10100).
 * Weaker arch-vile:The same as a regular arch-vile, except it has 500 hit points instead (type 22251).
 * Hectebus:A larger, black mancubus that rapidly shoots three volleys of twin green projectiles. It has 1500 hit points (type 22250).
 * Goat lord:The boss of the first episode, looking like a dark-skinned baron of Hell from Doom 64. It can fire three red fireballs in quick succession, and can also teleport around the arena, and if it teleports to the center, it becomes temporarily invulnerable as it is able to spawn demons, nightmare demons, or cause four turrets in the arena to launch homing fireballs at the player. It has 7250 hit points (type 10110).
 * Chaos elemental:The final boss, shown as a dark green and black pain elemental from Doom 64. It can fire multiple green fireballs, and in the arena it is fought in, it can also teleport to the outer area quickly to unleash fireballs from outside into it. It can furthermore activate seven green flamethrowers in the arena itself. It has 6500 hit points (type 10111).

Additionally, as part of the Rise of the Triad-themed secret map, several enemies from that game appear, including the low guard (type 20004), the lightning guard (type 20005), the strike team (type 20005), the high guard (type 23000) and the triad enforcer (type 23001), all behaving similarly to how they did in the original game.

Custom weapons
The secret level contains several weapons from Rise of the Triad, including the pistol and dual pistol, the MP40, the bazooka, the fire bomb and fire wall launchers. The last three weapon also come with their own ammo pickups.

Custom objects
Besides the weapons and enemies, several props from Rise of the Triad also appear, such as the spinblades and firejets, suspended platforms and jump pads.

Levels
Fortified Base Episode Pathway To Hell Episode
 * MAP01: Aegis Power Plant
 * MAP02: Waste Processing
 * MAP03: Hazard Storage
 * MAP04: Cargo Transfer
 * MAP05: Mechanical Labs
 * MAP06: Research Center
 * MAP07: Complications
 * MAP08: Central Security Grid
 * MAP09: Manufacturing Plant
 * MAP10: Power Core
 * MAP11: Refinery
 * MAP12: Courtyard of Ruin
 * MAP13: Abandoned Mine Shaft
 * MAP14: The Wastelands
 * MAP15: Drainage Plant
 * MAP16: Breakdown
 * MAP17: Fortress of Blood
 * MAP18: Deprivation
 * MAP19: Long Library
 * MAP20: Eternal Void (exit to secret map)

Director's Cut Episode
 * MAP32: In the Thick of It (secret map)
 * MAPX01: Delirium
 * MAPX02: Aegis Power Plant
 * MAPX03: Waste Processing
 * MAPX04: Hazard Storage
 * MAPX05: Cargo Transfer
 * MAPX06: Mechanical Labs
 * MAPX07: Twisted Way
 * MAPX08: Deprivation
 * MAPX09: Complexity

Soundtrack

 * MAP01: "Infinite" by Tom Mustaine, originally from TNT: Evilution
 * MAP02: "On the Hunt" by Robert Prince, originally from Doom
 * MAP03: "The Demons From Adrian's Pen" by Robert Prince
 * MAP04: "Demons On The Prey" by Robert Prince
 * MAP05: "Horizon" by Tom Mustaine
 * MAP06: "Suspense" by Robert Prince
 * MAP07: "Shawn's Got the Shotgun" by Robert Prince, originally from Doom II
 * MAP08: MIDI sequence of the Stage 3 theme from , originally composed by
 * MAP09: MIDI sequence of the Stage 2 theme from Journey to Silius, originally composed by Naoki Kodaka
 * MAP10: "Aliens, Say Your Prayers!" by Robert Prince, originally from Duke Nukem 3D
 * MAP11: "Where Izit" by Lee Jackson, originally from Rise of the Triad
 * MAP12: "Slow Evil" by Tom Mustaine, originally from Icarus: Alien Vanguard
 * MAP13: "Gotham" by Lee Jackson, originally from Duke Nukem 3D
 * MAP14: "Agony Rhapsody" by L.A. Sieben, originally from TNT: Evilution
 * MAP15: "Oww!" by Lee Jackson, originally from Rise of the Triad
 * MAP16: "Goin' Down the Fast Way" by Lee Jackson, originally from Rise of the Triad
 * MAP17: "Death's Bells" by L.A. Sieben, originally from TNT: Evilution
 * MAP18: "Untitled" by Robert Prince, originally from Doom
 * MAP19: "Sinister" by Robert Prince, originally from Doom
 * MAP20: "Mist Ache" by Lee Jackson, originally from Rise of the Triad
 * MAP32: "Suck This" by Lee Jackson, originally from Rise of the Triad
 * Title screen:, originally from 
 * MAPX01: same as MAP19
 * MAPX02: same as MAP01
 * MAPX03: same as MAP02
 * MAPX04: same as MAP03
 * MAPX05: same as MAP04
 * MAPX06: same as MAP05
 * MAPX07: same as MAP17
 * MAPX08: same as MAP18
 * MAPX09: same as MAP07