Taste of Power is one of Xanthe's Recruiters events. You break up a recruiting drive built on vrakhiri blood, then choose whether to take the blood or destroy it.
Speak to the Blood Guard, defeat the recruiters and open the golden box. Loot the Recruitment Instructions from the bodies.
Keeping the blood gives you a consumable. Destroying it sets Xanthe's court back instead. Either way the camp counts toward her anger.