In the Battle Tree, Trainers will use three Pokémon for Single Battles, four for Double Battles, and two for Multi Battles, all randomly selected from a Trainer-specific pool. In all Battle Agency challenges, the opponents will use three Pokémon.
Every Pokémon will have a randomly-selected gender and Ability, but stats are always fixed. Each Pokémon is assigned a Nature and EV distribution, along with its moves and item.
The Trainers listed here may be found at both the Battle Tree and Battle Agency. Different sets of Trainers will appear every ten rounds, increasing in difficulty each time until after 50. Within each range, Trainers are selected randomly with equal weighting.
Special Trainers appear only in the Battle Tree's Super Course challenges, during every ten battles. Like with the other Battle Tree Trainers, their teams are randomly selected from a group of Pokémon specifically preset for each of them. All of these Trainers are equally likely to appear except Anabel, who appears only one-seventh as frequently as everyone else.