**Chapter 4: Carnage in the Red Room**

The Red Room, a secret base hidden deep in the heart of the HYDRA organization, was Yelena's next target. She had received intel that the Red Room was a hub for HYDRA's most elite agents, and she aimed to take it down. With a deep breath, she focused on her mission. As she approached the base, Yelena triggered her Devil Trigger form. Her body transformed into a blue, humanoid demon with several white imprints detailed on her trench coat. The three coat tails separated into four, giving her an eerie, bat-like appearance when airborne. Her silky blonde hair changed into a crest with a fin shape at the top, and her neck gained a membrane that curved inwards. The spine merged with two dark-colored bones exposed at the top, and her sheathe altered and attached to her sleeve while becoming a clawed appendage. In this form, Yelena's eyes gleamed with an otherworldly energy as she charged into the base. The agents were caught off guard, and they didn't stand a chance against Yelena's skills. She sliced through them with ease, her summon swords flashing in the dim light of the base. The sound of clashing steel and the screams of the agents filled the air as Yelena made her way deeper into the base. Yamato, her powerful sword, shone brightly in her hand as she unleashed a flurry of attacks. The agents were slaughtered in seconds, unable to land a hit on Yelena. Her speed, precision, and discipline allowed her to outpace and utterly cut down her opponents as if it were an art form. With great concentration in only splits of a second, she issued a number of blows at her discretion, timing her victim's demise and sheathing in sync with the damage done. The display of destruction was a sight to behold, and it left the few surviving agents trembling in fear. The battle was over in a matter of minutes, and the Red Room was silent, the only sound the heavy breathing of Yelena as she stood victorious. She dispelled her Devil Trigger form, returning to her human form. The base was in ruins, and the agents were dead. Nick Fury, director of S.H.I.E.L.D., had been monitoring Yelena's activities, and he was impressed. He decided to show footage of her battle to the Avengers, hoping to gauge their reaction. The Avengers assembled in a high-tech conference room, and Fury played the footage on a large screen. The room fell silent as they watched Yelena take down HYDRA agents with ease. Her movements were fluid and precise, and her swordsmanship was unlike anything they had ever seen before. As the footage continued to play, the Avengers saw Yelena trigger into her final form - her Sin Devil Trigger. Her body transformed into a blue, humanoid demon with four wings folded down, and her sword arm mounted with blue blades. A thick reptilian tail with a barbed tip extended from between its shoulders, and her head resembled a traditional samurai helmet. The solid part of her body resembled samurai armor, and her whole body was wreathed in silver aura. The screen faded to black, and the room erupted into a cacophony of comments and questions. Yelena's skills and powers were unlike anything they had ever seen before, and they knew that they had to be careful around her. "Can we recruit her?" Iron Man asked, his eyes shining with interest. "I'm not sure that's possible," Fury said, his expression grim. "But I do know that we need to keep an eye on her. She's a wild card, and her powers could be a game-changer." The Avengers nodded in agreement, their minds racing with the implications of Yelena's abilities. They knew that they had to be careful, but they also knew that they couldn't ignore her. Yelena Belova was a force to be reckoned with, and she was about to change the game forever. "What we just saw was insane," Thor said, his voice filled with awe. "Her power is almost... divine." "It's not just her power," Captain America said, his eyes narrowed. "It's her skill, her strategy. She's a highly trained fighter, and she's using her abilities to take down HYDRA agents with ease." "But at what cost?" Black Widow asked, her voice laced with concern. "We're talking about a woman who can take down an entire room full of agents in seconds. What's her motivation? What's driving her?" Fury leaned back in his chair, his eyes fixed on the screen. "That's what we need to find out," he said. "We need to understand what makes her tick, and whether she's a potential ally or a threat." The Avengers nodded in agreement, their discussion continuing as they tried to make sense of Yelena's abilities and her place in the world. One thing was certain, however - Yelena Belova was a force to be reckoned with, and she was about to change the game forever.