Boosters can be purchased in the game Shop; some with gold, others with friend stones, and others using crystals. They can also be won as a prize when you play the Lottery. Most Boosters are always available in the Shop, but there are some that only become available during special sales or holidays.
The experience bonuses granted by Boosters stack on top of each other. So having multiple Boosters of the same Need (even if they're the exact same Booster) will add up and provide a bigger bonus.
List of Boosters
- A Booster that is only made available during Thanksgiving