Arrow: 10 Best Characters Who Only Appeared In One Episode

10. Aviva Metula/Shadow Thief

Due to its episodic format, Arrow saw obscure DC characters get the live-action treatment, and among them was Shadow Thief. The series chose to focus on the Aviva Metula version for its seventh season, and her backstory served that season's more grounded tone to some extent.

A former Mossad agent, Metula was renowned for her fighting prowess, her stealth and thieving skill. These attributes, coupled with her stealth-focused suit, made her the perfect mercenary for covert but high profile assassinations and thefts.

She eventually allied herself with Ricardo Diaz and the Laurel Lance of Earth-2 during the former's gradual takeover of Star City. Little over a year later, Metula returned to the city and goes on a crime spree with a now embattled Laurel.

Fortunately, Sara Lance, Dinah Drake and Felicity were able to convince Laurel to abandon her destructive path, a decision that led to Aviva setting off an explosive to secure her escape.

Her skillset and complete disregard for her partners (i.e. Laurel) helped solidify her guest spot on the series as one of the more well-done ones in the show's run.