2002 A Doom Odyssey

2002: A Doom Odyssey is a 2002 megawad for The Ultimate Doom which replaces all four episodes. The project was organized by Paul Corfiatis, who designed most of the levels, and also composed the megawad's soundtrack.

The megawad was first released on July 24, 2002. A second version was released on August 30, 2002, with changes to E1M3, E1M5, E2M2, E4M2, E4M5 and E4M6, as well as an additional level that can only be reached when the megawad is played in a ZDoom-based source port.

In 2003, it was listed as one of the top 10 WADs of 2002 in the Top 100 WADs of All Time article series during Doomworld's celebration of Doom's 10th birthday.

On July 30, 2004, a third version was released, with fixes to the megawad's MAPINFO lump, allowing every episode to be completed in ZDoom, as well as various fixes to certain levels. In addition, the secret exit definitions for E2M4 and E2M5 in the MAPINFO lump were switched, so that the player reaches E2M9 from E2M4 and E5M1 from E2M5, instead of the other way around. Unfortunately, the exit definitions for E2M9 and E5M1 (leading to E2M6 and E2M5, respectively) were not updated to match this, resulting not only in the player being unable to reach both secret levels in a single playthrough, and not only in the player being able to skip E2M5 by reaching and finishing E2M9, but in E5M1 taking the player back to the level they entered it from after finishing it.

For the tenth anniversary, a new update was released on July 27th 2012, though with a different file name (2002ad10) so as not to replace the previous. It added another new level and reshuffled some existing ones again. A minor bugfix for this tenth anniversary edition was issued on August 2, 2012.

Levels
Deep into the Code: Road to Eternity: The Evil Unleashed: The Search for Stephanie: Bonus ZDoom levels:
 * E1M1: The Entry by Paul Corfiatis
 * E1M2: Helicopter Bay by Kristian Aro
 * E1M3: The Doomed Lab by Paul Corfiatis (Exit to secret level)
 * E1M4: Substation 537A by Kristian Aro
 * E1M5: Combat Station by Paul Corfiatis
 * E1M6: Toxic Treatment Plant by Kristian Aro
 * E1M7: Service Base by Paul Corfiatis
 * E1M8: Paradox by Kristian Aro
 * E1M9: Lugano Base ZR-X by Paul Corfiatis (secret level)
 * E2M1: Station Alpha by Paul Corfiatis
 * E2M2: Station Beta by Chris Hansen
 * E2M3: The Lost Labs by Rory Habich
 * E2M4: Shotgun Blues by Paul Corfiatis (Exit to secret level; ZDoom-only)
 * E2M5: Fortress of Fatalities by Paul Corfiatis (Exit to secret level)
 * E2M6: Between Demons n' Insects by Rory Habich
 * E2M7: Puzzles to Solve by Kristian Aro and Paul Corfiatis
 * E2M8: Total Disturbance by Paul Corfiatis
 * E2M9: Dungeon of Hate by Paul Corfiatis (secret level)
 * E3M1: Gatehouse by Sam Woodman
 * E3M2: Caves of Bosnia by Paul Corfiatis
 * E3M3: Stronghold of Damnation by Rory Habich
 * E3M4: Hall of Ebola by Rory Habich
 * E3M5: De-Moon Side by Vick Bobkov
 * E3M6: Obituary Written by Chris Hansen (Exit to secret level)
 * E3M7: System Central by Paul Corfiatis
 * E3M8: Spider Temple by Paul Corfiatis
 * E3M9: The Lost Chord by Sam Woodman (secret level)
 * E4M1: Play School by Paul Corfiatis
 * E4M2: Back to Base X by Anthony Soto (Exit to secret level)
 * E4M3: Hell Unleashed by Chris Hansen
 * E4M4: Disreputable Stronghold by Chris Hansen
 * E4M5: Indomitable Haunt by Chris Hansen
 * E4M6: Dementia by Joe Pallai
 * E4M7: Odious Grounds by Chris Hansen
 * E4M8: Impossible Mission by Paul Corfiatis
 * E4M9: Secret Wolfenstein Level by Paul Corfiatis (secret level)
 * E5M1: The Mighty Green by Paul Corfiatis (E2 secret level, exit back to E2M5)

Soundtrack

 * E1M1: "Barrels n' Troopers"
 * E1M2: "What's around the corner?"
 * E1M3: "No fear!"
 * E1M4: "CityWoman choir"
 * E1M5: "Sexy!"
 * E1M6: "Rock it!, Cock it!"
 * E1M7: "Race Against Time"
 * E1M8: "Imperial Solutions"
 * E1M9: "Dance of the Trooper"
 * E2M1: "Banjo lovers delight"
 * E2M2: "Arch-Vile Cathedral band"
 * E2M3: "The Choice"
 * E2M4: "Popdoom"
 * E2M5: "Eternal sadness"
 * E2M6: "Hysterical horror"
 * E2M7: "Waltz of the Damned"
 * E2M8: "Totally evil"
 * E2M9: "Viva la Crypt"
 * E3M1: "Runaway Train"
 * E3M2: "Spirit world II"
 * E3M3: "Feel the pain!"
 * E3M4: "Skull of the Revenant"
 * E3M5: "Moonrise"
 * E3M6: "Intensity"
 * E3M7: "Backfire"
 * E3M8: "Gunshot Dance"
 * E3M9: "Party in Hell"
 * E4M1: "Arch-Vile Cathedral band"
 * E4M2: "Popdoom"
 * E4M3: "Viva la Crypt"
 * E4M4: "Hysterical horror"
 * E4M5: "Skull of the Revenant"
 * E4M6: "Eternal sadness"
 * E4M7: "Waltz of the Damned"
 * E4M8: "Gunshot Dance"
 * E4M9: "Get Them Before They Get You" (by Bobby Prince, from Wolfenstein 3D)
 * E5M1: "Surfin'"

Tenth anniversary edition
The 2012 update replaced the rather amateurish endgame screens and intermission pictures with screenshots of the levels. It also renamed episode 4 from "The Search for Stephanie" to "Torment Ultima". The original E4M1 was replaced by a brand-new one, E4M9 was shuffled to E5M2, E3M5 was shuffled to E4M9, and a brand new E3M5 was added. The original MIDI soundtrack was slightly tweaked; and nine new songs were added to give episode 4 its own original soundtrack. Some of the levels were subtly renamed.

This edition also fixed a major bug with Episode 2, which is one of the episodes with two secret exits. In the old version, E2M4 would send you to E2M9 and E2M9 always sends back to E2M6 so you'd miss E2M5 entirely. E2M5 sent the player to E5M1 and E5M1 send the player back to E2M5 again. So you could not play both secret levels in the episode, and either skipped or double-played E2M5 if you chose to take a secret exit, which was not an author intent.

In this version, E2M4's exit sends the player to E5M1 which properly returns to E2M5, while E2M5's exit is to E2M9 and returns properly to E2M6. Thus the secret levels cause no disruption in the normal progression of the episode.

E3 was also given a second secret level when the Wolfenstein level was moved out of E4. Exits here also head back to the correct levels.

Levels
Deep into the Code: The Road to Eternity: The Evil Unleashed: Torment Ultima: Bonus ZDoom levels:
 * E1M1: The Entry by Paul Corfiatis
 * E1M2: Helicopter Bay by Kristian Aro
 * E1M3: The Doomed Lab by Paul Corfiatis (Exit to secret level)
 * E1M4: Substation 537A by Kristian Aro
 * E1M5: Combat Station by Paul Corfiatis
 * E1M6: Toxic Treatment Plant by Kristian Aro
 * E1M7: Service Base by Paul Corfiatis
 * E1M8: Paradox by Kristian Aro
 * E1M9: Lugano Base ZRX by Paul Corfiatis (secret level)
 * E2M1: Station Alpha by Paul Corfiatis
 * E2M2: Station Beta by Chris Hansen
 * E2M3: The Lost Labs by Rory Habich
 * E2M4: Shotgun Blues by Paul Corfiatis (Exit to ZDoom bonus level E5M1)
 * E2M5: Fortress of Fatalities by Paul Corfiatis (Exit to secret level)
 * E2M6: Between Demons and Insects by Rory Habich
 * E2M7: Puzzles to Solve by Kristian Aro and Paul Corfiatis
 * E2M8: Total Disturbance by Paul Corfiatis
 * E2M9: Dungeon of Hate by Paul Corfiatis (secret level)
 * E3M1: Gatehouse by Sam Woodman
 * E3M2: Caves of Bosnia by Paul Corfiatis
 * E3M3: Stronghold of Damnation by Rory Habich
 * E3M4: Halls of Ebola by Rory Habich
 * E3M5: Blood and Guts by Paul Corfiatis (Exit to ZDoom bonus level E5M2)
 * E3M6: Obituary Written by Chris Hansen (Exit to secret level)
 * E3M7: System Central by Paul Corfiatis
 * E3M8: Spider Temple by Paul Corfiatis
 * E3M9: The Lost Chord by Sam Woodman (secret level)
 * E4M1: Unity by Paul Corfiatis
 * E4M2: Back to Base X by Anthony Soto (Exit to secret level)
 * E4M3: Hell Unleashed by Chris Hansen
 * E4M4: Disreputable Stronghold by Chris Hansen
 * E4M5: Indomitable Haunt by Chris Hansen
 * E4M6: Dementia by Joe Pallai
 * E4M7: Odious Grounds by Chris Hansen
 * E4M8: Impossible Mission by Paul Corfiatis
 * E4M9: De-Moon Side by Vick Bobkov (secret level)
 * E5M1: Surfing the Mighty Green by Paul Corfiatis (E2 secret level, exit back to E2M5)
 * E5M2: Secret Wolfenstein Level by Paul Corfiatis (E3 secret level, exit back to E3M6)

Soundtrack

 * E1M1: "Barrels n' Troopers"
 * E1M2: "What's around the corner?"
 * E1M3: "No fear!"
 * E1M4: "CityWoman choir"
 * E1M5: "Sexy!"
 * E1M6: "Rock it!, Cock it!"
 * E1M7: "Race Against Time"
 * E1M8: "Imperial Solutions"
 * E1M9: "Dance of the Trooper"
 * E2M1: "Banjo lovers delight"
 * E2M2: "Arch-Vile Cathedral band"
 * E2M3: "The Choice"
 * E2M4: "Popdoom"
 * E2M5: "Eternal sadness"
 * E2M6: "Hysterical horror"
 * E2M7: "Waltz of the Damned"
 * E2M8: "Totally evil"
 * E2M9: "Viva la Crypt"
 * E3M1: "Runaway Train"
 * E3M2: "Spirit world II"
 * E3M3: "Feel the pain!"
 * E3M4: "Skull of the Revenant"
 * E3M5: "Demon's March"
 * E3M6: "Intensity"
 * E3M7: "Backfire"
 * E3M8: "Gunshot Dance"
 * E3M9: "Party in Hell"
 * E4M1: "Lock and Load"
 * E4M2: "Mechanical Sadness"
 * E4M3: "Medieval Maniac"
 * E4M4: "Battle of Satanic Forces"
 * E4M5: "The Chase"
 * E4M6: "Dark Corner of Fear"
 * E4M7: "Hot Ash"
 * E4M8: "Confusing"
 * E4M9: "Moonrise"
 * E5M1:
 * E5M2: