Shigeru Miyamoto on where the concept of Super Mario Bros. came from…

“It wasn’t an idea that just came out of the blue. It was the culmination of a variety of factors. First, we had a lot of technical know-how built up from games like Excitebike and Kung Fu. Second, the Disk System [a Japan-only attachment] was coming out shortly, so I wanted to make a game that would put a final exclamation point on that era of cartridge games. Third, I wanted to build upon our tradition of what we called ‘athletic games’ at the time — games where you controlled a guy and had to jump a lot to overcome obstacles. We felt strongly about how we were the first to come up with that genre, and it was a goal of ours to keep pushing it.”

– Miyamoto on why Mario fights what are basically evil turtles in the game…

“Myself and [Gunpei] Yokoi were coming up with a gameplay concept for Mario Bros. that took advantages of the different floor levels of the playfield. Our idea was that direct contact with an enemy would kill you, but hitting them from below could knock them out. That wound up being too boring, so we settled on the final system where you first knock them off their feet, then jump back up to deliver the final blow. So Mario Bros. made it out, and after we reflected upon it, we realized it made no sense that you could get killed in Mario Bros. when you jumped on a turtle’s back. If you did that, the turtle would come out the worst from it, wouldn’t it? So we decided that, if we had the chance to make another Mario game, we’d definitely have it so that you could jump on turtles all you want.”

Miyamoto on the game’s controls…

“During much of development, the controls were A for shoot bullets, B to dash, and up on the control pad to jump,” said Miyamoto. “The bullets wound up becoming fireballs later — we originally thought about having a shoot-’em-up stage where Mario jumps on a cloud and shoots at enemies, but we dropped it because we wanted to focus on jumping action. The sky-based bonus stages are the remnants of that idea, you could say. In the end, we realized that being able to shoot all the fireballs you want while running gave Mario too much of an advantage, so instead we had it so you shoot only one fireball when you start running. That freed up the A button, and we made that the jump button. I really wanted to have A be the action button and make you press up to jump, but it definitely worked out better for Mario in the end.”

Miyamoto on why you power-up by grabbing magic mushrooms…

“One of the fun things about action games is looking at the game world and figuring out a strategy to deal with it. The first game prototype we had going wasn’t very good because you couldn’t see very far ahead of you. People wanted to have more of the world visible onscreen, but I didn’t want to make Mario any smaller than he was. So we decided to build the world on the scale of a smaller Mario, then make him larger in the final version. That’s the moment we struck upon the idea of starting Mario out small and letting him get bigger later. Since the game’s set in a magical kingdom, I made the required power-up item a mushroom because you see people in folk tales wandering into forests and eating mushrooms all the time. That, in turn, led to us calling the in-game world the ‘Mushroom Kingdom,’ and the rest of the basic plot setup sprung from there.”

Miyamoto on whether or not the 1UP trick was intentional…

“We did code the game so that a trick like that would be possible. We tested it out extensively to figure out how possible pulling the trick off should be and came up with how it is now, but people turned out to be a lot better at pulling the trick off for ages on end than we thought.”

Miyamoto on the Minus World…

“That’s a bug, yes, but it’s not like it crashes the game, so it’s really kind of a feature, too!”

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