This is how The Witch Doctor hypnotizes Rarity goes in The Witch Doctor's Revenge.
[Witch Doctor aims his staff at Rarity]
Witch Doctor: Watch my Skull Staff and you will do as you are told. You are Rarity. And that's a fact.
Witch Doctor: You will be my slave. Find what I need. And after then will you be freed.
[The Skull Staff glows and Rarity's eyes turn red]
Rarity: Yes. Master.
Witch Doctor: Now find me Quaza.
Rarity: Yes master.
Witch Doctor: Until now, I never realized how much fun this is. It's time for that fashionista to wake up. [to Rarity] You shall not be my slave now.
[Rarity shakes her head and her eyes turn to normal]
Rarity: What happened?