​When Space Invaders was created, the idea wasn’t for it to get faster or harder as you shot down enemies.
But there was a little problem: the console couldn’t handle that many aliens moving at once.

As you eliminated enemies, the system started breathing easier… and the game sped up. What started as a technical limitation became one of the most iconic mechanics in gaming: fewer enemies, faster gameplay.

And just like that, by accident, progressive difficulty was born a feature we now see in almost every shooter.

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