When the US and Russian Governments sent Natasha Romanova after the Deathless Frenzy, Yuri Stalyenko sent Yelena, at her own insistence, to shadow Natasha to ensure that the serum ended up in Russian hands. After being fooled into thinking Natasha was dead, Yelena headed to Rhapastan to stop General Khan and the Deathless Frenzy. She failed and was captured. It was only through the efforts of Natasha Romanova that Khan's plans failed, although Yelena learned some important lessons from her failing.
Shortly after, Yelena was used by Natasha in her plans to find out what General Stalyenko was up to. Yelena was captured from her home by S.H.I.E.L.D. agents and had a surgical operation where her face was swapped with Natasha's. Wandering New York in shock and being tricked by Natasha, Fury, and a reluctant Daredevil, Yelena nearly lost her mind. After the whole affair was over Natasha revealed that she had done this to try and help Yelena, yet Yelena felt the absolute opposite.
The Avengers were confronted by Yelena and a rogue S.H.I.E.L.D. battalion illegally mining vibranium in the Savage Land. They attacked the Avengers in order to kill them but an intervening Sauron burned Yelena's upper body severely. Once in ICU she was offered a way to take revenge on what happened to her and eventually kill Spider-Woman in the process.[1] A mysterious man approached her with AIM scientists in tow, promising to make her more powerful than before, even more powerful than the Avengers, which would make her the new Adaptoid.
Months later, just prior to the wedding of Luke Cage and Jessica Jones[2] Yelena attacked the Avengers in their tower. The nature of the Adaptoid's powers made her unconquerable by her new ability to host every power she´d been attacked with. Although strengthening herself by taking in the Sentry´s powers, she weakened herself by also taking in the Void's.
Now when the mysterious man behind this scheme saw that Yelena wouldn´t be able to kill Spider-Woman, thus becoming disposable, he pushed the remote fail-safe button and killed her.
Yelena later turned up alive and was working for a vigilante named the Vanguard.
After the Secret Invasion, Norman Osborn approached Yelena when she was stealing from an abandoned S.H.I.E.L.D. facility. However, this Yelena turned out to be Natasha, the original Black Widow in disguise under Nick Fury's order to infiltrate the Thunderbolts. However, Osborn had in fact known all along who she was and used her to strengthen the bonds of his Thunderbolts, and lead him to Fury and Songbird to be executed.
After Natasha and Songbird managed to escape, while Fury was revealed to be a LMD, Osborn decided to awake the real Yelena, who had been kept in stasis within the Avengers Tower.
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