Happiness (also known as friendliness, friendship and loyalty) is needed to evolve certain Pokemon, the use of certain movies outside of battle, and determines the power of some moves inside of battles.
There are a few different ways to improve the happiness of your Pokemon.
- EV Reducing Berries (+2, +5, or +10 depending on current happiness.)
- Vitamins (+3)
- HP Up
- PP Max
- PP Up
- Rare Candy
- Friend Ball (Pokemon starts with 200 Happiness)
- Haircuts (+3) – Located in Goldenrod Underground (Johto – NPC Old Harry) and Black City (Unova – NPC Conker)
- Juice – Located in Black City (Unova – NPC Betty)
- Massage – Located in Castelia City, Pikachu House 11F (Unova)
- Leveling Up (+5)
- Soothe Bell (increase happiness gains by 50%)
Letting your Pokemon die in battle will cause it’s happiness to drop.