Perhaps you're thinking of one of these items:
* Poké Balls: Used to catch Pokemon.
* Great Balls: Higher chance of catching Pokemon than Poké Balls.
* Ultra Balls: Even higher chance of catching Pokemon than Great Balls.
* Master Balls: Guarantees catching any Pokemon.
* Premier Balls: Special Poké Balls given as rewards.
* Luxury Balls: Special Poké Balls that make caught Pokemon happier.
Please clarify what you mean by "spheres" and I'll be happy to help!