Even Pokemon Snap, released in 1999 for the Nintendo 64, was based on offering players a maximum of photo opportunities of Pikachu and friends.

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Travelling with the message is an attachment that, when clicked, launches animation of a bouncing Pikachu - the yellow mouse-like Pokemon that fights with electricity.

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But at the same time that the Pikachu is bouncing around the screen the program is also making changes to a key configuration file on the PC.

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