Thane Krios

"The measure of an individual can be difficult to discern by actions alone." 

Thane is a drell assassin, rumored to be the most skilled in the galaxy. Unlike most assassins, who prefer to snipe their targets from a distance, Thane likes to get up close and kill his target personally, utilizing a mixture of stealth, firearms and biotic abilities. Despite this approach, he is cool and calculated in his work. Though adept at his profession, Thane experiences strong feelings of guilt about his job and prays for himself after each kill. Firmly believing this act of penance should never be forsaken, Thane will even go as far as to ignore those in his immediate vicinity until he is finished doing so.

Commander Shepard first confronts Thane on Illium, where he is on a mission to assassinate Nassana Dantius. As Shepard is talking with Dantius in order to discern the assassin's whereabouts, Thane drops from the ceiling and takes out Dantius' bodyguards before killing her with a pistol shot at point-blank range.

Trivia

 * Thane may be named for the historical Scandinavian and Anglo-Saxon term used to describe either a high ranking nobleman or a class of retainer.