Roark is Byron's son and runs the Oreburgh Mine alongside his gym leader duties. He's known for using Rock-type Pokémon, and players who take him on will face his Geodude and Onix, both at level 12, plus a Cranidos at level 14. In the anime, that Cranidos eventually evolves into Rampardos. Beat him and you get the Coal Badge.
You'll need to track him down in the mine before you can challenge him officially—he's usually there doing supervisor stuff. He's also the one who greets you when you first head into the Underground.
Content compiled by AnimeList.moe from publicly available sources.
