Sierra

Sierra was a demon that served Asmodeus after his return.

History
After the disappearance of Lucifer, Sierra is in Crowley's former lair with several other demons as they argue about what to do. Suddenly, the Prince of Hell Asmodeus arrives and announces that he is in charge until Lucifer returns. Asmodeus calls forward Drexel, Harrington and Sierra before smiting the rest of the demons in the room. Sierra later watches as Asmodeus explains to Drexel about his attempt to release the Shedim.

While Asmodeus takes Jack to release the Shedim, he leaves Harrington and Sierra to kill the Winchesters and Donatello Redfield.

Powers and Abilities
Harrington appeared to be a regular low-level demon with all the powers of one.
 * Demonic Possession - As a demon, he needed a vessel to walk the Earth.
 * Immortality - As a demon, he would never age or die unless killed.
 * Invulnerability - As a demon he was invulnerable to normal methods of harm.
 * Super Strength - As a demon, he was stronger than humans and most monsters. In a fight with hunter Dean Winchester, Sierra was able to effortlessly throw Dean around the room and break his hold when Dean pins him to a table.

Weaknesses
As a regular low-level demon, he possessed all the weaknesses of one.
 * High-Tier Demons - He was subservient to and weaker than higher ranking demons such as the Prince of Hell Asmodeus.
 * Angel Blade - Sam was able to kill Harrington with an angel blade.

Appearances

 * Season 13
 * The Rising Son