Friendship is a hidden relationship value between a trainer and a Pokémon. It can increase through actions such as walking, leveling up, using certain items, grooming systems, and keeping the Pokémon from fainting. It can decrease through fainting, bitter medicine, or other game-specific actions. Some Pokémon evolve when they level up with high friendship, sometimes only during day or night. Friendship can also affect a small number of moves and features. Friendship is not the same as affection in every generation, even though later games sometimes combine or display related systems. Check the particular game’s method before grinding friendship.
