Vorta

Vorta is a member race of the Dominion. One family of then-primitive Vorta once saved one of the Changelings, the rulers of the Dominion. For this, they were genetically engineered into an intelligent species thoroughly loyal to the Changelings and act as Dominion administrators, field commanders, scientists, and diplomats. They have direct authority over the Jem'Hadar and are tasked with dispensing doses of Ketracel White to them.
In 2017, Den of Geek ranked the Vorta the 15th best aliens in the Star Trek franchise