Trainers can choose any Pokémon in their team as the "Buddy Pokémon". The Pokémon will be shown next to trainer's avatar. Only one Buddy Pokémon can be selected, but it can be changed anytime. When travelling with the Buddy Pokémon, 1 Candy for the Evolution Chain can be gained by walking the distance that is set for each Pokémon. So that, Trainers have the chance to power up or, if possible, evolve the rare Pokémon they have. Also there is the "Size" attribute that indicates where the Pokémon will be positioned next to the Trainer. For instance, a Pokémon with "Big" size will be shown behind the Trainer, whereas a "Medium" Pokémon will be positioned by the side of the Trainer.