DOOM is often considered the granddaddy of first-person shooters, and that's not hyperbole. Starting over 30 years ago in 1993, DOOM has to be the longest-running first-person shooter franchise that actually started out as an FPS.
Wolfenstein and Duke Nukem only went into the FPS genre, starting with the third installment. The original game still holds up, so it should be no surprise that the franchise remains ongoing with new entries. Unlike most other game series, there isn't one black sheep, as all the DOOM titles are good. However, some are better than others and much more worth playing. Only the mainline games count here, so there will be no DOOM RPG, DOOM VFR, or Mighty DOOM.
8 DOOM 2: Hell On Earth
Bigger, But Not Better
DOOM 2: Hell on Earth has a far greater legacy for what it did to the DOOM community than the actual game itself. The positives to DOOM 2 are the new content, mainly the new enemies, and one new weapon added. All the new monsters are great, except for the generic Hell Knights, and the Super Shotgun is probably the best weapon in all of Classic DOOM. The Arch-Vile has to be my favorite DOOM enemy. Unfortunately, most of the levels are awful and incredibly dated compared to what the DOOM community has built since then.
John Romero, primarily responsible for what made Shareware DOOM such a groundbreaking title, only made six maps for this game. They're some of the best, too, with The Living End and Industrial Zone. Most of the levels were designed by Sandy Petersen, and they have aged like milk. Just look at Downtown, with its obvious pointing arrow, straight out of a fourth-wall-breaking spoof. Then, there are levels like The Chasm, which wasn't even good at the time, with its tightrope walking. Most of the game just doesn't hold up to current DOOM standards.
7 DOOM Eternal
The Better You Are, The Worse It Gets
The second title in the modern DOOM series, DOOM Eternal, has a lot going for it, but there's a reason it's this low in the ranking. First off, the positives. The level design is fantastic, with great Easter eggs to discover; the soundtrack's amazing, and the Master Levels are a blast for hardcore players. The hub area is awesome, too. Unfortunately, there are two big issues with DOOM Eternal.

DOOM Legend John Romero’s Favorite Shooter Is This Ubisoft Game That’s Nothing Like His Classic FPS
John Romero's brought one shooter up on multiple occasions as his particular favorite, and it isn't a game that I would have ever guessed.
The main issue is the core gameplay loop of glory kills, flame belch, and the chainsaw. This has to be the biggest gameplay problem because once you get good at DOOM Eternal, it gets boring, as you are doing the same thing repeatedly. What makes FPS games like DOOM fun is the on-the-fly gameplay, switching weapons to match the current situation. However, this gameplay loop restricts you to doing the same mechanics repeatedly.
To boot, the multiplayer is atrocious. DOOM 2016's multiplayer wasn't that great either, but at least id never gave up on it and improved the online play with various DLC packs and additions. I played about two online matches in DOOM Eternal and never returned. It was that bad. If the multiplayer were absent, I would probably bump up Eternal a few spots higher, but as is, it's the second-worst game in the series.
6 DOOM 64
The First Spooky DOOM Game
Before DOOM 3 tried its hand at a more horror-focused take on the series, there was DOOM 64. The atmosphere, lighting, visuals, and terrifying music by Aubrey Hodges do a lot in giving DOOM 64 its own unique feel. It's refreshing compared to all the other Classic DOOM games. The maps here are superior to DOOM 2, but not on the same level as Knee-Deep in the Dead or The Plutonia Experiment. You can still get lost at times.
DOOM 64 is an all-around solid game, but why's it so low on this list? Besides the new horror feel, there's nothing really special about it. It's Classic DOOM with a new paint job, and while I like the horror feel, I prefer the older visuals. DOOM 64 introduced the Unmaker, an excellent secret weapon, so much so that it inspired the Unmaykr in DOOM Eternal.
5 DOOM 3
The Long Grind
DOOM 3 is a very love-it-or-hate-it game in the DOOM community. First, there are two versions: the original (available on GOG) and the BFG Edition (available on Steam and modern consoles). I played the BFG Edition, which is available on Game , so keep that in mind, as I've heard the original is far superior. I'll it I didn't like this game at first. DOOM 3 has to be the longest game in the series, even more so than The Dark Ages.

DOOM: The Dark Ages - How To Find Every Secret In Hebeth
DOOM: The Dark Ages' second level, Hebeth, has nine secret areas containing a mixture of upgrade material, collectibles, and valuable resources.
The first half of this title is very slow, with more of a horror focus, but around halfway through, and especially when you enter Hell, DOOM 3 gets into high gear. When you have all the weapons and the game's throwing hordes of monsters at you, it's a phenomenal FPS that feels great to play. It's a shame it took so long to get to that point. Thankfully, the expansions improve this pacing issue and get into the intense FPS action far quicker. The title's a must-play DOOM game, but make sure to stick with it.
4 DOOM: The Dark Ages
A Big Improvement, For The Most Part
The newest game in the series, DOOM: The Dark Ages, lives up to the hype. Dark Ages ditches the gameplay loop of Eternal for a more traditional style but with a twist, as a significant focus is on the Captain America-style shield used to parry attacks. Unlike titles like Clair Obscur: Expedition 33, where the combat revolves around parry mechanics to such a high degree, DOOM: The Dark Ages uses parries as often as it should.
The Dragon sections, in particular, are a lot of fun with great controls, and they must be in future DOOM games.
Parries are required to survive on higher difficulties, but in order to properly dish out enough damage, you must use your actual weapons, and there are a ton of great ones to pick. The campaign here is very long, and like DOOM 3, it gets into high gear a little over halfway through. However, unlike DOOM 3, Dark Ages mixes up the gameplay with Atlan and Dragon sections. The Dragon sections, in particular, are a lot of fun with great controls, and they must be in future DOOM games.
There are some negatives, like the lack of quality Easter eggs, Master Levels, or a Hub area, but for the most part, DOOM: The Dark Ages improves upon DOOM Eternal, and it also helps that there's no lackluster multiplayer this time.
3 DOOM 2016
The Game That Put The Franchise Back On The Map
After going through development hell, DOOM 4 eventually became DOOM 2016, one of the best FPS games of the generation. DOOM 2016 brought that classic boomer shooter feel back into the triple-A space, and it was about time after the jetpack era of FPS games back then. It felt like Classic DOOM with some new twists, like the glory kill system, which was a huge innovation for FPS games. Duke Nukem Forever actually had healing executions in 2011, but it's not about who did it first. It's about who did it best.

DOOM: The Dark Ages Fixes Eternal's Melee Problem & I Couldn't Be Happier
DOOM Eternal's melee attacks were one of the game's less exciting features; luckily, DOOM: The Dark Ages' new mechanics have completely changed that.
The campaign is still a blast, even with Eternal and Dark Ages now out. One can argue that the campaign of DOOM: The Dark Ages is superior, but the reason I'm placing DOOM 2016 higher has to be the total package. You get online multiplayer, which is significantly improved from when at launch; there's a full-blown arcade mode and even bonus levels that mimic stages from Classic DOOM. DOOM 2016 also has great Easter eggs, and I think the level design is superior to DOOM: The Dark Ages.
2 Final DOOM
Go 4 It
As a long-time DOOM fan, I'm pleased to see the public's perception of Final DOOM change over the years. Final DOOM contains two 32-map megawads: TNT Evilution and The Plutonia Experiment. If The Plutonia Experiment was the only megawad included, Final DOOM would be the best DOOM game ever made. The Plutonia Experiment is the best Classic DOOM campaign bar none, with mastercrafted level design that's brutal but fair. The game throws so many monsters at you, but one can't help but love its challenge and incredible FPS action.
Final DOOM introduced the first real slaughter map with Go 2 It in Plutonia. Unfortunately, there's also TNT Evilution. This megawad isn't as bad as everyone says, but it's still not good. The first half is pretty decent, with great levels like Stronghold and Dead Zone, but once you're on map 16, the quality goes off a cliff. The only good map past number 16 is Heck, not to mention that TNT has the worst level in the entire DOOM series with Habitat. Despite all this bad content, Plutonia makes Final DOOM the second-best game in the series.
1 DOOM 1993
One Of The Greatest Games Of All Time
A few game series, like God of War, just can't beat the original, and the same applies to DOOM. The original DOOM, specifically the Shareware version, is the most important FPS game ever made. Knee-Deep in the Dead still holds up in the FPS genre, even regarding current DOOM standards. Beginner mapmakers will often get redirected to look at Knee-Deep in the Dead for how to make quality DOOM maps, and that's a testament to how John Romero nailed Episode 1 of DOOM.

DOOM: The Dark Ages - How To Find Every Secret In Village Of Khalim
DOOM: The Dark Ages' first level, Village of Khalim, has seven secret areas containing a mixture of collectibles, and valuable in-game resources.
John Romero designed seven out of the nine maps in Episode 1, and they're still so much fun at all skill levels. The number of hit scanners was a brilliant design move. It made the game fun for both newcomers and people cranking up the difficulty to Nightmare mode. Episodes 2 and 3 aren't nearly as good, but the quality returned in Episode 4. Thy Flesh Consumed was designed after id made DOOM 2, and you can tell the designers improved here.
It still blows me away how timeless Knee-Deep in the Dead is, especially with how badly DOOM maps have aged with DOOM 2 and TNT. In hindsight, releasing the best levels in the game for free may not have been a good idea, as most didn't bother purchasing the full title back then. However, it's thanks to this nine-map Shareware release of DOOM that the FPS genre became what it is today.