Space Invaders accidentally invents difficulty curves

When someone says “retro arcade game”, there’s a pretty good chance that a picture of one of these little blocky aliens pops into your head. 

1978’s Space invaders was so influential that even Shigeru Miyamoto, the creator of Nintendo’s cornerstone franchises, has pointed to it as the game that “revolutionized the industry“. 

Like all retro games, the key is that it’s effortless to start playing, and next to impossible to master. At the beginning, the alien ships are just lined stupidly in front of you in rows. You just have to pick them off with your laser, right? ah, but as you decimate their numbers, something happens: They go faster. 

It made for an absolute perfect difficulty curve. success was rewarded with greater challenge. The more aliens you killed, the harder it got. And when you got down to those last few aliens, you had to have lightning reflexes

The thing is, the scaling difficulty was totally unintentional. The entire game was programmed and built by one man: Tomohiro Nishikado. And by built, I mean that he spent an entire year custom developing the hardware for the game because the hardware available in japan at the time wasn’t powerful enough to run it. It was like the Crysis 2 of 1978. 

And when it was all finished, Nishikado discovered that the hardware still wasn’t powerful enough to run the game how he intended it. He programmed the game to move all the liens at what he thought would be a pretty steady rate, but while play testing it, he found the aliens to be quite a bit slower than he wanted. There were simply too many on the screen for the hardware to handle, so it bogged down. 

As he played on, however, he discovered that the game sped up as he brought swift laser-justice to those invading alien bastards, fewer characters for the processor to keep track of meant it could finally move them at their correct speed. He liked the effect so much, he decided to keep it, saying it “added more thrills to the game

Actually, you could argue it added the only reason to keep playing the game at all. It was the first game that actually got more difficult as you progressed. Before that point, games were pretty much the same all the way through (often repeating the same screens over and over), and it was basically a matter of waiting for your hands to get tired. 

This combined with the fact that it was the first game to implement a high score system meant that dedicated people put a lot of quarters into space invaders – it actually created a yen shortage in Japan

Read other modern gaming trends created by glitches at this link.