My life as a youngster with a top percentage Rattata was much more successful than I expected? - Pokemon SI

The top percentage Rattata was a legendary existence never before proven to work in the highest levels of professional battling, or any level of professional battling to be honest. But, Joey, a reincarnated youngster, was willing to pull all the stops into making this dream a reality and make his partner ascend into the realm of champions. A pre-canon self-insert.