When DOOM was released in 1993, no one could have predicted how it would change the game industry, nor how long it would last. New levels, mods, and total conversions for the first-person shooter are still being made today on the DOOM 30th anniversary.
The moddability of DOOM (and DOOM II, which is also approaching its 30th birthday having come out only a year after the first game) comes down to the way its data is structured. The game data that makes up a level is stored separately to the game engine that makes it all work, which makes it possible to replace the graphics, level designs and sound effects to create, effectively, a new game.
This data is held in a WAD file, which is rumoured to mean ‘Where’s All the Data’. Making DOOM (and later DOOM II) an easy-to-modify game was backed from the start by two of id Software’s leading lights, John Carmack and John Romero. Carmack has moved on from DOOM to work in VR and AI, but Romero continues to create DOOM levels, with his SIGIL considered the unofficial fifth episode of the game, and the upcoming SIGIL II the sixth.
DOOM mods can go much further than simply changing the demons you’ll shoot in Hell to pictures of your mother, though that’s completely possible. Total conversion mods can make big changes, altering the setting, storyline, characters and more. They can turn what today feels like a simplistic shooter into something much more complex.
You’ll need the PC version of the game to play these, as the console ports generally don’t allow you to monkey around with the game files, and many of them are works in progress, recieving regular updates and new content. As with all fan-made mods, there’s no guarantee they’ll work, and may require a specific version of the original game. Here are some of the best.
From Brazilian developer Marcos Abenante, aka Sergeant Mark IV, this mod ups the gore level of DOOM. It also adds some features that id itself would use in the 2016 DOOM reboot and later DOOM Eternal games – blood spatter, stealth kills, and finishing moves that echo the newer games’ glory kills.
As such, it’s an even more violent variant of the game – something further enhanced by new weapons such as flamethrowers and a grenade launcher.
This DOOM II mod was released in 2023, and converts the game into an immersive walkthrough of a haunted house. You can tell it’s still DOOM thanks to the coloured keycards, and the fact you need to defeat monsters, but Myhouse plays with the rules of the DOOM engine itself as well as the ways time and space work, with journal entries to read that can be accessed through a Google Drive folder that add context to the horror.
This total conversion brings the Aliens universe to DOOM, and it’s a great fit. It brings four classes of Colonial Marines to play as against the xenomorphs, as well as Weyland-Yutani company forces, mercenaries, and malfunctioning combat droids. Each class gets its own story and side missions, while weapons and enemies are inspired by the Alien movies as well as the Alien Trilogy PlayStation game.
John Romero returned to the game he co-created in 2019 for an unofficial fifth episode to mark the game’s 25th anniversary, which brings nine missions’ worth of demonic chaos accompanied by a soundtrack from prolific and unusually-crowned guitarist Buckethead. Romero wanted to make SIGIL more difficult than DOOM‘s previous episodes, while still feeling like they belonged there, and also mixed up the style of the levels, with bigger lava pools and a lot more pentagrams scattered around the place.
This conversion mod brings the atmosphere of Stalker: Shadow of Chernobyl or Metro 2033 to DOOM II, providing a post-apocalyptic world overrun with radiation, vicious mutants, and marauding gangs to fight.
A survival horror mod for DOOM II, set on a remote island known as Fort Oasis. The island was once home to a community of coal miners who one day suddenly disappeared, leaving behind an abandoned concrete jungle to waste away – until you follow a mysterious radio transmission and wash up on its shores.
The original mod has spawned a standalone version based on the Unreal Engine 5 that takes the graphics way beyond what the DOOM engine is capable of. It’ll probably take a little while before it’s done, however, so check out the game Turbo Overkill, by the same creator, instead.
Sonic Robo Blast 2
Somehow avoiding Sega’s lawyers, this DOOM mod recreates the original Mega Drive Sonic games in 3D. Instead of scrolling forever sideways, you get free movement in all directions, multiple player characters, the chance to play with up to 32 players online, and customisable levels. There’s a Sonic Kart version too.
An attempt to merge all versions of DOOM into one game, this mod also has a randomiser that mixes up the placement of enemies, powerups and weapons so you don’t always play the same levels every time. There are new enemies and weapons based on those from more modern DOOM games, plus extra visual effects.
A weapons and gameplay mod for DOOM and DOOM II, Combined Arms brings “outlandish and unorthodox weaponry” to the game such as a bow and arrow, sharp-shooting rifles and energy pistols, across four packs of new guns and melee weapons. There’s also an optional addon with new monsters, which are said to be a touch more aggressive than the standard DOOM beasties.
This mod for DOOM II sounds like it should be about the First World War, but it really isn’t. Celebrating its third anniversary in 2023, Trench Foot sends you, as Master Templar, the enforcer of the one true faith, into battlefield trenches filled with disease, radiation, and 15 types of new enemy to take down with the holy instruments at your disposal.