I do not own the Avengers or High School DxD. One-shot.

A stray devil sluggishly crawls away to save her life, but the wounds sustained in battle only hardens her escape. She knew she would eventually be hunted down for rebelling against her master. She thought the devil king's younger sister, Rias Gremory, and her peerage would be the ones to go after her, but she never expected… that thing to suddenly appear from a portal of unknown origin. She used all her tactics available to her, but she never once denting or scratching its metallic armor. One by one, her bone broke with each punch that thing delivered. Even using a magic shield, its punches shattered through them like they were made of glass. And now, all she can do it crawl away as her legs are severely broken into multiple fragments with her conqueror standing over her, slowly approaching her.

"My scans indicate while you maintain a human presence, you are not human, but another flawed biological organism." It states in a matter-of-fact tone, giving the impression it knows what it is talking about. "True, you are able to perform fleets impossible for humans and make use of magic, as you call it, but still are flawed like any other biological organism, but do not worry yourself. I will correct this." With all options extinguished as it stands over her, all she can do is turn around and face her destiny.

"W-who are you…" She manages to squeak, coughing up blood in the process, staring down at it crimson glowing mouth.

Issei Hyoudou narrowly escapes the blast of red-glowing, destructive energy fired at him, striking the ground instead. Dodging the attack gives Issei the right moment to counter attack, but he could not will himself to attack for he recognizes the attack.

"I-Impossible…" Rias Gremory utters in disbelief as she too witnesses the eerily familiar attack. Both the Red Dragon Emperor and the Princess of Ruin along with the rest their friends watch in disbelief, confusion, and horror as the crimson-haired beauty and attacker preps for another attack as her arms glow with the power of destruction.

"P-president." Issei finally manages to state, indicating there are two Rias Gremorys as Issei looks back and forth to ensure his eyes are not deceiving him.

"What kind of sorcery is this!?" The original Rias inquires of the fake Rias before her; however, she does not answer as the look in her eyes are only content with defeating her opponents before her.

"I don't think its sorcery. All I can smell from that fake Rias is metal." Koneko Toujou answers.

"Metal…" Asia Argento repeats.

"Stop." With that utterance, the fake Rias Gremory energy surrounding her hand slowly dissipates and assumes a neutral position. What unnerves Rias and her friends more is the motion of her actions. The way she moves is still like any other person, but the way she executes that order is somewhat reminiscent of a robot.

"I can assure you this is no sorcery." A voice clarifies from the shadows.

"Show yourself." Rias orders. Heavy footsteps echo from behind the fake Rias as she remains perfectly still. The shadowed, silhouetted figure soon takes place with a red glow coming from the person. As the person draws closer, they start to realize the person towers over all of them as he stands at an imposing 8 feet tall. The fake Rias remains as she as her master slowly approaches.

"What the hell is that?" Issei inquires as a silver-colored machine appears behind the fake Rias. It looks around the room as it recognizes all the people before him, or it.

"To answer you last question, it is not sorcery, but rather a scientific achievement I accomplished in no more than two days, Rias Gremory."

"That's impossible! There is no way you could mimic my powers!" Rias rebels.

"Maybe for an imperfect, biological organism, but not for me, However, I did not limit myself to your power only." It states as more footsteps echo from behind it.

"No way…" Rossweisse exclaims as she, along with the rest of the peerage, marvel at their doppelgangers. "Kiba, Xenovia, Akeno, Gasper, Koneko, Issei, and Asia."

"W-who are you?" Asia is the one to ask the silver-colored enemy. It looks over to her and stares at her for the longest of time before Issei jumps in between his gaze and Asia.

"I am Ultron Prime, and these is my Synthezoids." Ultron answers. One by one, each Synthezoid arms themselves with their respective powers and abilities: S. Kiba with a holy devil sword, S. Xenovia with a holy sword, S Akeno with lighting surrounding her, S. Rias with the Power of Destruction swirling around her, S. Gasper with his eyes glowing, S. Koneko with cat ears and tail popping out as it calls fourth her nekomata powers, but he biggest surprise and danger is S. Issei performing a balance breaker as the armor of the Red Dragon Emperor covers the S. Issei's body. 'They are identical in every way to the original, however…." The only one who doesn't arm itself is S. Asia, who approaches Issei. She, or it, gazes at him. Issei, on the other hand, is still in disbelief as the S. Asia is standing before him, knowing full well she is the enemy, but an enemy who looks exactly like his most cherished friend. S. Asia cocks her right arm back, and without missing a blink, fires her fist straight, connecting to the Red Dragon Emperor, sending him flying through a wall. "I have made improvements that makes them better than the flawed, organic originals."

"Issei!" Asia and Rias cry out.

"Synthezoids, Attack!"

What do you think. Reviews are encouraged.

**This story is not connected to Aftermath. This is me just gauging something new. Ultron is my most favorite villain from Marvel (If you look at my past stories, you'll see a lot of them surround Ultron directly and indirectly). I have not read the comics, so I am trying to understand how powerful comic book Ultron would be in a DxD universe. From what I saw from a video about Ultron's strengths, he is quite powerful and intelligent. Would he steamroll through everybody, or would he be comparable to the Devil kings?