Ava and her friend Jayden watched on T.V. as the COO of Stane/Stark Enterprises, Ezekiel Stane introduced the first international Captain America to the public, Shannon Carter. Ava became annoyed with the thought of people thinking that this woman was for real. She knew who the real Cap was, and when Jayden mentioned Steve Rogers she impulsively said no, the one Tony Stark brought back was the real deal, Frank Castle.
Jayden didn't know who Ava was talking about, so she took him to where he lived, just around the block. When they got there, all Jayden saw was this old man in sweat pants taking out the garbage. He laughed at the thought of who this guy might be, so he got back on his bike telling her he wasn't going to waste his time believing her. As he took off the old man threw the garbage lid at Jayden with such strength and precision resulting in him falling off his bike.
Ava knew that he was Frank Castle even though he denied it. She asked him if he could teach her how to throw the lid like he did and in exchange she wouldn't bother him ever again. He agreed to her deal, and showed her how to throw it to the point where she shattered a glass bottle in half. He then told her maybe he was who she thought, but those days were long gone and America didn't need him anymore. Years passed as she waited for his return but it never happened, so she trained herself hard, which provided her with the chance to be injected with the serum. She became the latest Captain America and leader of the Captain Americorps.
Ava's planet was next invaded by Ultron-1320 from a parallel world which caused a temporal paradox involving four other Earths. She was pulled through the portal to Earth-45162 along with other heroes from the different realities. Together they battled Ultron with the help of the Wasp and Goliath of this reality but couldn't overtake Ultron and his Sentinels. They then came across Ultron-1321, who was the Hank Pym from the world that Ultron was spawned from.
He devised a plan to keep Ultron stuck in the current reality and send Ava and the others to his home reality of Earth-14622 so he could make up for his mistakes. They managed the trip through with Ava telling Natasha to use her hammer to close the rift. Now on a barren planet with no life, the heroes still carried on to become the Avengers Infinity.