Video games have changed so much over the years and it’s led to many popular genres dividing and becoming more specific. This is especially true for shooters, which have grown in substantial ways since the early days of PC gaming. First-person shooters have always led the way in the genre and the Doom franchise has largely been at the head of the movement and helped define what a FPS could be.

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Doom is known for its precise gameplay, memorable level design, and its powerful and disturbing demons, but it’s not always a series that makes logic or deductive reasoning its priority. The Doom games are an entertaining and chaotic time, but they don’t always make sense.

10 Doom Guy’s Past And History

Id Doom Doomguy Classic Costume

The Doom titles tend to focus more on gameplay than story, which has actually resulted in the series’ protagonist, Doom Guy, turning into a fascinating cipher. The series operates as if it’s the same Doom Guy in each game, but the backstories teased in the original Doom and Doom II: Hell on Earth are very different. The original Doom Guy fought on Mars and Phobos before he reaches Earth, whereas Doom II claims the character fought on the UAC Mars Base and then left via drop ship. These histories don’t align or it’s possible that they’re actually different Doom Guys.

9 Sometimes Doom Guy Has A Name

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One of the more clever things that John Romero did with the original Doom is that he decided to intentionally leave the Doom Guy protagonist without a name so the player could feel more immersed in the FPS experience. That being said, supplemental Doom material have conceded that the character’s name is actually William “B.J.” Blazkowicz, or Billy Blaze for short. This moniker doesn’t exactly mesh with the rest of the franchise and raises further questions considering that the protagonists in Wolfenstein 3D and Commander Keen are also known as William Blazkowiczs. The Doom novels also name him Flynn Taggart.

8 PDAs Are The Wave Of The Future

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The original Doom titles feature similar gameplay, but they’re each radically different in terms of where they’re set. Doom 3 features a major departure from the previous titles as it’s set not only in the year 2145, but also on Mars. A recurring feature through Doom 3 is the gathering of information through scattered PDAs.

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PDAs are the dominant form of technology, which seems highly suspect since they were practically obsolete by the time of Doom 3’s release in 2004. There would have to be many concessions with superior technology in order for PDAs to still be important in 2145.

7 The Loss Of Weapons And Equipment Between Levels

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Video games sometimes go to painstaking efforts to create a feeling of authenticity, but there’s still often “video game logic” that restricts certain mechanics that audiences just learn to accept. Doom tells a cohesive story across its levels, yet each new stage begins with Doom Guy’s weapons and equipment vanishing as he’s re-stocked with a basic pistol and ammunition. This mechanic is shed in Doom II, but it returns in Doom 3. The use of teleportation lends itself to plausible answers, but the games offer no explanation for why certain items just vanish from Doom Guy’s arsenal.

6 Commander Keen Characters Are Present

Id Doom II Hell On Earth Commander Keens Hanging

Developer Id Software was groundbreaking for their work in the shooter genre during the '90s and even though Doom and Wolfenstein get the most attention, they also found a lot of fans with their Commander Keen series. Doom II: Hell on Earth is full of many secrets and hidden areas, but the most elusive area of them all revolves around Commander Keen. The player has to shoot down four hanging figures in order to unlock Doom II's secret level. These four characters are actually Commander Keen, which raises all sorts of questions that are more trouble than they're worth.

5 Doom Guy’s Face On Magazines And Arcade Machines

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Doom 3 is a very wild entry in the series that doesn’t hold back in any department. Doom 3 celebrates the franchise’s past and there are some Easter eggs in the game that are satisfying for fans, but don’t exactly make sense in the context of the Doom universe.

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For example, there’s an occasion where a magazine is found that has the Doom Guy making a shocked expression from the original game. There are also arcade cabinets that are branded with Doom Guy. There’s no reason why this figure would be treated like a celebrity of this nature.

4 John Romero Appears In The Game

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The development of video games was a substantially smaller affair back in the ‘90s and it’s always a lot of fun when developers or creators will find a way to secretly engage with their audience. There are many extreme examples of this, but one of the most audacious is that John Romero, the creator of Doom, actually appears in Doom II: Hell on Earth. Romero shows up as a disembodied head that actually speaks to the audience, albeit in reverse. This hidden feature is not easy to discover, but it makes even less sense that Romero would be in this world, let alone that his severed head can still speak.

3 Doom Guy's Pop Culture Lava Death

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The Doom series and the Terminator films strangely share some overlap. Accordingly, it's not a total surprise to see the Doom games pay tribute to the movies, but that doesn't mean that it makes sense. In both Doom (2016) and Doom: Eternal, if the player keeps Doom Guy in lava until their health completely drains to zero then they'll give a thumbs up as they sink into the magma. It’s unlikely that Doom Guy is familiar with Terminator 2, but it'd be impossible for him to stand in lava to pull this off without immediately melting or expressing pain.

2 Wolfenstein 3D Layouts Are Replicated

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Doom is a pivotal piece of gaming history, but before its release id Software had already brought the first-person shooter genre to life with exciting properties. Wolfenstein is now with Bethesda, but it was id Software’s first major shooter and Doom II: Hell on Earth finds an unexpected way to honor the game. There are two bonus levels in Doom II that are recreations of the first and ninth levels in Wolfenstein 3D. This is a fun connection, but realistically there's no way that these locations in Doom II would be identical to the layout of something from Wolfenstein.

1 Doom Demons Are Nine Inch Nails Fans

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The Doom series has cultivated a very metal aesthetic over the years, especially in regards to its music. The Ultimate Doom is an expansion on the original game that sometimes gets overlooked. The Ultimate Doom adds a new Episode 4 to the package and its first mission contains the logo for the band Nine Inch Nails on one of the level’s walls. This a nice reference to id Software’s eventual relationship with Trent Reznor, who would come up with Quake’s score, but it likely has the Doom Guy scratching his head.

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