instigator
noun [ C ] uk/ˈɪn.stɪ.ɡeɪ.tər/ us/ˈɪn.stə.ɡeɪ.t̬ɚ/
(尤指坏事的)发起者;煽动者
a person who causes something to happen, especially something bad
The instigators of the disturbance have not yet been identified. 目前还没有确定这起骚乱事件的煽动者。
Synonym: initiator