Every loyal Doom fan knows of the Masters of Doom: John Romero and John Carmack. Romero led a life in the spotlight and was responsible for being the personality of the franchise. Carmack, on the other hand, was the spirit of the series. Living up to their personas, Romero was always visible, being discussed by presidents, senators, world leaders, and businessmen whenever a face had to be placed on a product.

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Yet all firsthand accounts confess that Carmack was the one who made Doom run. He is famed for his reclusive nature, his genius, and his monkish discipline. His impact on the gaming world goes so much deeper than these descriptions, and facts about his life should be of interest to any gaming historian who wants to see how the video game industry went from a gimmicky trend to a global phenomenon.

10 First Sentence

Young John Carmack At Work With Boxes

Carmack was an unpredictable genius at best. His parents noticed he wasn't speaking and grew concerned. They considered that perhaps he had a learning disability despite him learning to walk and eat earlier than scheduled.

One day, John's father asked his mother where the sponge had gone. John walked into the kitchen, grabbed the sponge, returned, and said his first words, "Here's your loofah, daddy." John did not seek to show off something he hadn't mastered first. This would manifest later in life when he didn't make an arena shooter unless it could be one of the best arena shooters.

9 Psychological Persuasion

John Romero And John Carmack Holding Medieval Weapons

Carmack was never violent towards anyone, but that wouldn't stop others from diagnosing him with some kind of mental condition. As he explored video games and programming in his childhood, his parents intervened.

They hired psychologists to convince him to pursue "normal" computer work after seeing some of his violent sketches. Instead of stopping him, they fueled him. These drawings would be the earliest iterations of the horrific demons that would manifest in the Doom games later on.

8 Dungeons & Dragons Enemies

id Software Team Carmack And Romero

Why are the boss fights in Doom so hard? John Carmack has the answer to that question. He was a natural dungeon master for his groups that played Dungeons & Dragons. His team loved his sessions, but the monsters were unforgiving.

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During a campaign with the guys from Softdisk (before they became id Software), the group wiped out against a bunch of Carmack's demons. As they discussed ideas for Doom, they remembered the difficulty of the demon horde that killed them and decided those should be the game's primary antagonists.

7 Bill Gates Recognition

John Carmack Working At Computer

Carmack was recognized for his brilliant mind well before his contributions hit the main stage. Doom Eternal has plenty of secret activities for curious players to discover; likewise, the man behind the series was discovering the secrets behind coding.

Bill Gates saw the potential of John Carmack and called him a "genius." Were it not for the call of video games, it was very likely at one point that Carmack would have gone into generic software programming for the multi-billionaire.

6 On Government Radar

John Carmack Video On A Podcast

Having left to pursue other possibilities in the video game world, Carmack is no longer working on the Doom franchise (though the developers over at Doom Eternal have plenty of problems they'd like him to fix).

Saying goodbye to id Software was hard, but it was not the first goodbye he'd have to deliver. The US government requested copies of his work for the military and asked him to consider joining. Luckily for gamers, Carmack remained committed to gaming.

5 Super Mario Brothers 3 Port

John Carmack Speaking At A Convention

One night, Carmack stayed behind to play around with some coding. The problem with playing on a PC was that it was considered impossible to play games that scrolled; there was a piece of the programming that would not allow it.

That was when he invented a way around this limitation called "adaptive tile refresh." It was so effective that he ported all of Super Mario Brothers 3 onto the PC in a single night. He showed the port to the people at Nintendo, who congratulated him, but said no thanks to the technology. Too bad, they could have used his mind to fix some of those wild N64 glitches.

4 Rocketman

John Carmack Reading From Book At Quakecon

Computer science wasn't the only expertise for Carmack. Even before the days of the great flight simulators, he loved to study and build rockets. He had access to the model rockets designed for his classmates, but Carmack preferred bigger models that he made himself.

As an adult, Carmack made plans for a "Vertical Dragster" and worked with a team of local rocket enthusiasts to put a large vehicle into space. They never ended up manning it, but they did successfully launch a rocket of this size on multiple occasions.

3 Accessibility Pioneer

John Carmack Explaining AI To A Child

Before "accessibility" became a standard word in the lexicon of gaming, John Carmack was thinking about how those with impairments would be able to fully experience his games. It was truly only conceivable by a mind like his.

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Programming challenges weren't enough. Carmack was replacing entire engines. When he wasn't upgrading an engine, Carmack would look back on his work and gave himself a new challenge; make it so his games can be played by more people. His efforts laid the framework for modern programmers to answer this call.

2 Multiple Attacks

John Carmack In Formal Attire Headshot

Gamers that run face-first into Doom Eternal's Marauder know that it has a whole arsenal of moves: A summoned dog, a sword chop, a shotgun, a shield, and a beam. Without Carmack, his attack would be limited to only one of these.

John looked at the pixels in the games he played and experienced tediousness when they were predictable. He was the first programmer to give enemies more than one attack, opening up an endless evolution for his team and the industry at large.

1 Secrets About Secrets

John Carmack At Doom Movie Premier

John Romero insisted that Doom have secrets. Carmack vocally disagreed. He gave all kinds of excuses about how these hidden push walls were impossible and players would not think they were fun or be able to find them. Romero reluctantly capitulated.

At some point, Carmack changed his mind, but he did not tell Romero or anyone else on the id Software team. As they turned in their work for publication, Romero remarked that the game would have been better with secrets. Carmack told Romero he agreed... and that he had already programmed them into the completed product.

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