Riolu is a bipedal Fighting-type Pokémon introduced in Generation IV. It's known as the "Emanation Pokémon" and is prized for its inner strength. It has a blue body with short legs and a pointed tail. It has black markings around its eyes and on its chest, and three red points on each foot. It can sense auras and is said to be able to predict attacks.

Lucario is the evolved form of Riolu. It is a Fighting/Steel-type Pokémon known as the "Aura Pokémon." It is much more humanoid than Riolu, with a long, black and blue coat and a metal chestplate. It has red and black markings on its face, and three-toed feet. Lucario is known for its powerful aura abilities and its loyalty to its trainers.