The Trail to the Pokemon League
This campaign uses a d6 system. I got the inspiration from the Star Wars d6 campaign system, and altered it to fit the video game statistics of Pokemon, using http://pokemondb.net as the standard for the base stats.
All stats start with 2D. For every 10 points in the base stat, add one pip, with 30 points making up 1D (Mewtwo has 154 Special Attack, which translates to
2D + (154 / 30) D
2D + ~5D*
*for extra units, round to the nearest ten.
Mewtwo has 7D Sp. Att.)