All of us have fond memories of playing great games in our childhoods. Well, did you know that someone in another part of the world might have played the exact same game, but it was entirely different!? Welcome to the wonderful world of localization.
Probably the most famous and well known example of a completely different game as a result of localization is Super Mario Bros 2. After the release of the original Super Mario Bros, Nintendo of America not only had a MASSIVE hit on their hands, they now had a character that was synonymous with the Nintendo name. NoA was chomping at the bit to get a sequel for the hugely popular game released in the US. However, upon finally receiving a playable version of the sequel from Japan for testing, the management at NoA was astounded at what they had actually received. Terrified that this game was not only punishingly difficult but looked exactly like the original Super Mario Bros, and fearful of the damage a bad sequel could cause, NoA made a strange request of their Japanese parent company; Give us something more user-friendly, along with a different game design for a Mario sequel.
Faced with a very odd request, the creative heads of Nintendo of Japan decided to use a game they currently had in development and re-work it into a Mario game. The game that was chosen was "Yume Kojo: Doki Doki Panic" or "Dream Factory: Heartbeat Panic". The game's title and characters came from a joint collaboration between Nintendo and broadcaster Fuji Television. While the characters themselves were owned by Fuji TV, the game itself was the property of Nintendo, making it the perfect choice for conversion into a Mario game. All they had to do was create some new character sprites and make some adjustments to the overall difficulty and an entirely new Mario game was born.
The Western version of Super Mario Bros 2 was such a success that Nintendo of Japan eventually released the game in Japan as "Super Mario Bros USA". Likewise, the original Super Mario Bros 2 would also see release in the US as part of the "Super Mario Bros All-Stars" collection under the name "The Lost Levels."
Interestingly enough, it is a direct result of Nintendo of Americas request for a different and easier Mario game, that they forever changed how the Mario franchise would play. Can you even imagine a world in which Mario, Lugi, Peach and Toad don't play differently? Well if it wasn't for NoA and the game known as "Yume Kojo: Dokidoki Panic", that might just have happened...