10 Video Game Bugs That Became Features

8. An Accidental Revolutionary Difficulty Mechanic - Space Invaders

This bug which became a feature is not only the oldest example on this list and possibly the most iconic, it fundamentally changed the way games were played. And it happened as a result of a mistake.

In 1978 the release of Space Invaders set the stage for the games industry in a whole host of ways. It inspired some of the greatest games to come and some of the most intrinsic mechanics in the genre. It also had a fascinating approach to difficulty that would change the way that difficulty mechanics worked in games, but this approach actually began as a glitch. This isn’t to put down the incredible work of Tomohiro Nishikado who even created his own hardware with which to run the game. Unfortunately, Nishikado still couldn’t get his aliens moving as fast as he wanted them to as the processor couldn’t keep up.

Of course, once the player started defeating aliens, the processor had an easier time rendering aliens and as a result the sprites’ movement sped up.

Inevitably this increased speed made them more difficult to hit thereby making the game trickier the more you played and the more you succeeded. Nishikado was clever enough to see this as a win and kept it in the game, establishing the first example of a dynamic difficulty curve.