Gamers of a Certain Age will Recognize this Immediately
Ahh, the good ole Konami code. Nintendo Entertainment System gamers will remember this to get thirty lives in Contra or a fully powered ship in Gradius. It's one of those things that when we get to the age where we forget our own birthday, we'll still remember the code, Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start. There is an interesting history to why this exists and how it was used after it's NES days.
The Konami Code was created by Kazuhisa Hashimoto who was working on bringing Gradius from the arcades to the NES. The game was so difficult that Hashimoto had a hard time testing the game. He created the code to fully power the ship to make things a bit easier. It was never meant to be left in the game, though. It was discovered after the game was ready for retail production. It was left in because it would have delayed the game and also would have caused some other bugs and glitches.
They figured because of the complexity of the inputs, it would be near impossible to enter accidently while playing, so the code stayed.
Where the code really took off was in the game Contra. Inputting the code before the title screen fully appears will grant thirty lives to the player. Most needed the boost to finish the very difficult game. The sequel, Super C, uses a version of the code, Right, Left, Down, Up, A, B, Start, to give the player ten lives. If you were playing with two players, pushing Select before Start will give both players ten lives.
Since then, the code was utilized in other Gradius and Contra games and in Castlevania, Teenage Mutant Ninja Turtles, Metal Gear and other Konami franchises. Other game companies would use the code as an easter egg during gameplay. Wikipedia has a full list of all the games that use the code and what benefit it adds.
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