If one has a friend who has the game as well, could he/she just delete their Pal Pad and pass by you again right after and continue until you get to 1000? If the challenge allows you to do it over time and not get 1000 at the same time?
3DS FC: 1075 - 0819 - 0953 Pokemon White Version 2 FC - 2838 7984 6351
They don't have to 'delete their pal pad' they just have to pass by you 'x' times. Where 'x' is the number of times needed for the medal.
For example, you could pass by each other once a day. Or, multiple times if you turn your game on and off (saving before turning off of course). Or, moving in and out of each others wireless range (approx. 10-15 feet, more or less depending upon local conditions*).
* Such as interference from Microwaves, Cordless Phones (including mobiles), older Bluetooth devices (usually those that were designed before the 2.1 spec), and certain other devices. Or impeding materials such as certain types of Brick and Metal.
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