I'm sure a lot of you are familiar with the infamous Nuzlocke challenge, but if you aren't I've added a picture for you all to rest your eyes upon. It has the rules. Basically, every time I get a new game I do the Nuzlocke challenge for my first run through, I guess it makes the game a lot more interesting. I've also learnt, from this challenge, not to depend on the starter you receive in the beginning of the game! I find it a fun challenge, I've even earned $450 for doing it!
I've also done the Pidgey challenge, which needs no picture. It speaks for itself. Complete the game using a single Pidgey, you may catch Pokemon to use as HM slaves but that is it. They aren't allowed to fight, only the Pidgey.
What challenges do you guys use?! and why?!