Developer id Software is back to making sequels significantly more difficult than their predecessors. The reboot DOOM (2016) was likely meant to draw players back to the franchise, while the sequel tests players' skill. While a series like Dark Souls is becoming progressively easier, DOOM has done the opposite. With difficulty names like "Hurt Me Plenty" and "Ultra-Nightmare," DOOM Eternal is not meant for the faint of heart.

RELATED: 10 Hardest Enemies In Doom Eternal

The following games are brutally more difficult than DOOM Eternal. It's not a question of if, but when you'll die. You may as well quit while you're ahead. Here are a few first-person shooter games harder than DOOM Eternal.

Updated by Jack Pursey on February 6th, 2021: One aspect of DOOM that some players were worried about id Software removing was the range of tough difficulty levels. Thankfully, id Software didn't hold back and provided one of the most grueling FPS challenges in recent memory with DOOM (2016) and then ramped it up even further with DOOM Eternal. The positive reception that the game continues to receive has given the FPS genre a boost in popularity, so we've decided to expand this list to include more games that will push players' FPS skills to their limits.

15 System Shock 2 (Impossible Difficulty)

The fact that System Shock 2 even has a difficulty setting labeled "Impossible" should be enough of an explanation as to why Electronic Arts' title earns a spot on this list.

With a Metascore of 92, System Shock 2 is one of the most critically acclaimed first-person shooters of all time. The game is reminiscent of BioShock, which was also developed by Irrational Games (2K Boston), due to the game's eery atmosphere, sense of being stranded, and innovative combat mechanics that would influence the gaming industry for years to come.

14 Duke Nukem 3D (Damn, I'm Good Difficulty)

Understandably considered to be the most successful DOOM-clone of all time, Duke Nukem 3D was released in 1996 by the team of 3D Realms and FromGen to critical acclaim, predominantly due to its destructible environments that were unique for the time.

Duke Nukem 3D didn't hide its DOOM influences and tried to one-up id Software's original two titles with its Damn, I'm Good difficulty level that caused enemies to respawn much like DOOM's Nightmare setting.

13 S.T.A.L.K.E.R.: Shadow of Chernobyl (Master Difficulty)

The first entry in the S.T.A.L.K.E.R. series, S.T.A.L.K.E.R.: Shadow of Chernobyl was released in 2007 to a positive critical reception, exemplified by its 82 Metascore. The game was praised for its realistic post-apocalyptic survival gameplay and RPG mechanics that players need to pay close attention to if they want to survive Master difficulty.

RELATED: The 10 Hardest Action Games Ever Made, Ranked

A sequel, titled S.T.A.L.K.E.R. 2, is confirmed to be in development. Very little has been heard about the upcoming game, other than the news that it will be coming to Game Pass for the Xbox Series X|S on day one of its release.

12 Operation Flashpoint: Red River (Hardcore Difficulty)

Operation Flashpoint: Red River was released in 2011 by Codemasters, and is still one of the most realistic Tactical Shooters on the market today. The game didn't perform particularly well with critics, exemplified by its PC Metascore of 67, though it did offer a uniquely intense co-op experience.

Operation Flashpoint: Red River's difficulty comes from enemies being able to kill players with just one bullet; this may seem extreme even for hardcore mode, but believe it or not, this is the case with normal difficulty too. Hardcore mode still manages to find a way to ramp up the challenge even further, by removing the player's HUD.

11 ArmA II (Expert Difficulty)

From one Tactical Shooter to another, ArmA II was released in 2009 by Bohemia Interactive and is a successor to Operation Flashpoint: Cold War Crisis, which is now known as ArmA: Cold War Assault. Similar to the Operation Flashpoint series, running and gunning simply isn't an option, as players must opt for careful, methodical squad tactics if they want to survive.

Much like the aforementioned Operation Flashpoint: Red River, playing on the hardest difficulty removes some of ArmA II's key features, such as the handy third-person mode.

10 Metro 2033 (Hardcore Difficulty)

Metro 2033 seems to be more difficult than its successor, Metro: Last Light. There aren't very many people who would recommend diving into the hardest difficulty right away.

If you purchase the DLC, you can unlock two more difficulty modes that are even more demanding. The three standard difficulty modes should be enough for you to question your gaming skill. You'll have to be hard as nails to get through Metro 2033 on Hardcore difficulty.

9 GoldenEye 007 (00 Agent Difficulty)

Not only is it difficult to defend against tumultuous enemies with an array of weapons, but you must also achieve a list of objectives to beat any given level. This list of mission objectives grows with each difficulty increase. Finally, you get to 00 Agent, the hardest difficulty in GoldenEye 007 (aside from the 007 customizable difficulty).

RELATED: GoldenEye 007: 10 Behind-The-Scenes Facts & Trivia You Never Knew About The Iconic N64 Game

If you're like many people, you probably resorted to using cheat codes to progress. Even on Agent difficulty, many players will find levels like Frigate, Complex, Jungle, and Caverns an arduous experience.

8 Halo 2 (Legendary Difficulty)

Some would argue that Halo: Combat Evolved is the most challenging Halo game to date. Grenades that detonate in succession can make Halo: Combat Evolved a tough game.

However, with enemies that can one-shot kill you, Halo 2 is unquestionably the most difficult game in the series. Try playing it on Legendary with a friend on co-op; you won't survive. Halo 2 is long and tedious. If you can beat the first level alone, you have FPS skills that few others possess.

7 Metro Exodus (Hardcore Ranger Difficulty)

If the original Metro games weren't difficult enough, the newest entry added a new difficulty level. As you may have guessed, it's harder than all previous difficulty levels in the series. It's called Hardcore Ranger, and it disables the HUD (heads-up-display).

You'll have to rely on stealth to progress through the game on Hardcore Ranger since bullets can kill you in one shot! This is the ultimate challenge for Metro Exodus players.

6 Counter-Strike: Global Offensive

Although many would agree that Counter-Strike: Global Offensive isn't the most difficult game to pick up, it is tremendously hard to master. As a game with an online-focus, its most elite players will lay you to waste with certainty.

RELATED: Doom Eternal: 10 Important Tips & Tricks For Beating Ultra-Nightmare

Counter-Strike: Global Offensive uses a keyboard and a mouse with many players utilizing different mouse sensitivities. A player could be moving at a laser pace while you are on the default setting. Moreover, veterans have been playing the game for years, so don't be discouraged if you are a humble Silver rank.

5 Far Cry (Realistic Mode)

The original Far Cry was not as accessible to gamers as the newer games are. However, Far Cry 5 can also be a challenging game. The consensus is that Far Cry 5's first level is next to impossible, but the rest of the game is doable.

The original Far Cry is a gong show and a nightmare from which there is no waking. It's possible to beat this game on Realistic Mode; it's just highly unlikely you'll survive.

4 Star Wars: Dark Forces (Hard Difficulty)

Star Wars: Dark Forces is a masterpiece, but the hard difficulty takes things to a whole new level. The shooting mechanics aren't the most developed. Essentially, Star Wars: Dark Forces is the Star Wars version of Doom. Both games are from the MS-DOS era and feature similar gameplay. It's almost like the developers designed the hard difficulty without the intention of people beating it.

RELATED: 10 Games To Play If You Loved Star Wars Jedi: Fallen Order

Did you know that Star Wars: Dark Forces loosely inspired the film Rogue One: A Star Wars Story? Play the game, and you'll know what we mean.

3 Doom (1993) (Nightmare! Difficulty)

The original Doom released in 1993 is a different game than the new reimagined DOOM and DOOM Eternal. Since they both come from the same series, it's only natural to try to compare them. It can be said with certainty that the original Doom is harder than DOOM Eternal.

In an era where FPS gameplay mechanics were being developed, MS-DOS games were influenced by the arcade era. Arcade era games were designed to suck as many quarters out of you as possible, which is one reason why they were so tricky. It wasn't until years later that games became appealing to a broader player base.

2 Call Of Duty: World At War (Veteran Difficulty)

The bullets fly and you hit the floor, hoping that you can live to fight another day. Call of Duty: World at War pushes players to their limits by having a tremendously difficult Veteran difficulty.

While other games are demanding for their sophisticated A.I., Call of Duty: World at War gets nitty-gritty by significantly increasing enemy damage. Grenades are tossed into the battlefield, making every step like walking into a minefield. This game is almost impossible on Veteran difficulty.

1 Doom II: Hell On Earth (Nightmare! Difficulty)

The debate continues to go on about which Doom is the most difficult. Some of the top contenders are Final Doom, DOOM Eternal, and Doom 64. Developer id Software played it conservative with the first Doom to establish a fan base, yet they were relentless in creating the sequel.

As a series renowned for unforgiving gameplay, it poses a challenge, especially for those born in the '90s and onward. '80s gamers are cut from a different cloth. They can progress through games like Doom II: Hell on Earth because it's second-nature to them. Doom II: Hell on Earth's name is descriptive of its difficulty. The first game gives you chances to defeat enemies, but the second Doom is too hard.

NEXT: DOOM Eternal: 5 Things We Will Experience In The First DLC (& 5 Things We Might See Later)