Natalia Romanova (Earth-6457)

"How many more jobs... How long will it take... I don't know if I can do it... Even if I could forgive myself... This is what I am now. And you'll never know who I was before."

- - Black Widow to Captain America

Natalia Romanova (Черная канарейка) AKA Black Widow, is the greatest spy and assassin in the whole world. Orphaned during the Battle of Stalingrad, she was taken upon Red Army sniper Viktor Reznov, who raised her as his own daughter until his death two years after World War II. Enlisting in the Red Army at age 15, she was eyed by GRU, soon joining their ranks and becoming a spetsnaz, until she was chosen by the MGB as one of the candidates of the Black Canary Program, which trained young girls through Russia and made them perfect assassins for the Soviet Union during the Cold War. She was the only one to survive until the end, being injected with a special serum that gave her superhuman strength, reflexes, speed, stamina and longevity.