Get every the first 7 badges and defeat Team Rocket at Goldenrond

Trading It.  Remember Some Pokemon don't appear in your version, the same way as with mine.  I have one I found it after catching SUDOWOODO on a piece of Grass before Eucrateak.  By the way I'm using HeartGold that's how I got one

You only get one or you can always use the Action Replay.... Warning: It can corrupt your system.