<Li> knock out gas </Li> <Li> tear gas pellets </Li> <P> Black Widow (Russian: Чёрная вдова, transliterated Chyornaya Vdova) (Natalia Alianovna "Natasha" Romanova, Russian: Наталья Альяновна "Наташа" Романова, also known as Natasha Romanoff) is a fictional superhero appearing in American comic books published by Marvel Comics . Created by editor and plotter Stan Lee, scripter Don Rico, and artist Don Heck, the character first appeared in Tales of Suspense No. 52 (April 1964). The character was first introduced as a Russian spy, an antagonist of the superhero Iron Man . She later defected to the United States, becoming an agent of the fictional spy agency S.H.I.E.L.D., and a member of the superhero team the Avengers . </P> <P> Scarlett Johansson portrayed the character in the films Iron Man 2 (2010), The Avengers (2012), Captain America: The Winter Soldier (2014), Avengers: Age of Ultron (2015) and Captain America: Civil War (2016) as a part of the Marvel Cinematic Universe franchise . </P>

When did black widow first appear in mcu