Trainers pokemon are able to level up by defeating wild pokemon and other trainer's pokemon, as per usual. There is a difference in our way of leveling up. Observe:
Defeated pokemon's level is lower: 1/4 experience added to your pokemon's XP bar.
Defeated pokemon's level is the same: 1/2 xp added to your pokemon's XP bar.
Defeated pokemon's level is higher: 1 level up.
When a pokemon is ready to evolve, it must follow these rules:
If a pokemon must be traded or have a high friendship with the owner: add fifteen (15) levels to the previous evolution level.
If a pokemon is in its first stage of evolution: the pokemon will evolve at level twenty five (25).