Wild, trainees, anyone with a Pokemon can be challenged from what I can tell. When you win against gym leaders they give a badge, like an awkward kind of boy scouts of America thing. Get 8 from one region you can battle the top four trainers of the place. So yeah, a lot like sports.

[Finishing his drink, Tony digs into his jeans pocket and pulls out a small ball, taping the centre it gross and then he casually tosses it and the large steal bird comes out with a trill then just stares at Steve and Grace.]
He's a Skarmory. Just a big metal bird. Normally starters evolve, but they don't have to. She just doesn't have an evolutionary path. Her name's Dummy 2.0.