The phrase "wert in power of" refers to being under the control or authority of someone or something. Some synonyms for this phrase include being in the grip of, being held by, being subject to, being subservient to, being under the thumb of, and being at the mercy of. Other similar phrases that can be used include being dominated by, being under the control of, being ruled by, being overseen by, being managed by, and being directed by. All of these phrases signify the idea of being under the influence of another, either willingly or unwillingly.