Natasha Romanoff, also known as Black Widow, is a highly skilled spy and assassin in the Marvel Cinematic Universe. In Avengers: Endgame, she plays a crucial role as a member of the Avengers, working tirelessly to reverse the effects of Thanos' snap. Her character is known for her intelligence, combat prowess, and deep sense of loyalty to her friends. Throughout the film, Natasha shows great determination and selflessness, ultimately sacrificing herself to obtain the Soul Stone, enabling the Avengers to restore the universe.