Blue Oak (Pokémon Adventures)

Blue, full name Blue Oak, is a deuteragonist of the Red, Green & Blue, Gold, Silver & Crystal, and Emerald arcs of Pokémon Adventures. He was also a protagonist in the FireRed & LeafGreen arc. He normally serves as a rival and friend to Red. It is revealed that Blue trained under Chuck, the gym leader of Cianwood. Therefore, he knows a lot of martial arts.