Cathleen Bate/Synopsis

History
Many years ago, a young Cathleen Bate was travelling with her family on their way to the Santa Monica pier when they got caught in the middle of a villain attack. She was terrified and prayed for at least her little sister to survive, however, they were all saved by a Japanese foreign exchange student, who would become All Might. From that day on, she became inspired to become a hero just like All Might, seeing him as her role model.

Once she was an adult, she entered military training and later became a Pro Hero, eventually rising through the ranks to become the No. 1 Hero in the United States, thanks to her Quirk, New Order. However, during her training days, she did everything she could think of to boost herself to All Might's level, but she was never able to bypass the limitations of her Quirk. Her fellow soldiers, who would later go on to be her teammates, would console her about her insecurities, telling her about how great she already was.

At one point Cathleen became the hero Star and Stripe, and became the number 1 hero of the U.S.A. During her time as a Pro Hero, the U.S. government tried to keep the specifics of how her Quirk exactly worked a secret.

Tartarus Escapees Arc
After the events of the Paranormal Liberation War, the hero society of Japan had fallen, with escaped villains rampaging throughout the streets, many heroes going into retirement, and the masterminds behind it all, All For One and Tomura Shigaraki, still at large. In desperate need of aide, the remnants of the hero governments sought out assistance from the foreign heroes to provide backup.

This was accelerated to a desperate response when All Might learned that Tomura was to be completed faster than they initially believed, personally calling for help. While the rest of the nations debated amongst themselves whether they'd be able to provide assistance, Star and Stripe, alongside an army of fighter jets, almost immediately made their way over to Japan to rendezvous with the Pro Heroes and help her "master."

Current Arc
While in the airspace nearly to their destination, Star and Stripe and the fighter jets were met faced against "Tomura Shigaraki" riding a flying Nomu, as she asks him if he is the villain known as "All For One." One of the pilots corrects her, telling her it is actually Tomura, as the jets proceed to deploy shock shields and take formation to fight. Star and Stripe shouts that they're ready to fight, and tells the pilots she'll bring their remains back to their loved ones if they fall.

"Tomura" comes at his opponents with a multi-Quirk attack, using Radio Waves, Air Cannon, and Heavy Payload to release an enormous wave of electric energy toward them, which they manage to dodge. Star and Stripe and "Tomura" both trade taunts with each other, as she confidently decides to unleash her Quirk, declaring that "the air does not exist 100 meters ahead of me."

Suddenly, the air all around "Tomura" completely disappears, forcing him to hold his breath. Star and Stripe notes that if he's facing against her he wouldn't go down that easily, and orders the fighter jets to shoot lasers at him, which they fire at all angles directly into him. She warns the pilots not to be cocky, as sure enough, "Tomura" uses a combination of Reflect and Scatter to disperse the lasers back at the jets.

Star and Stripe uses her Quirk to safely catch the laser, while everyone notices "Tomura" regenerating, realizing that is why the Japanese heroes lost against him. Creating a new rule also results in the air around "Tomura" returning, which he takes advantage of to blast his way forward right towards her.

However, Star and Stripe simply punches "Tomura" in the face, smacking him into one of the jets, as she proclaims to him why she was inspired by All Might to become a hero. He's annoyed that once again everything comes back to All Might, which she says is why he is the Symbol of Peace to begin with. After touching him and saying his name, she declares "If Tomura Shigaraki moves at all, his heart will stop."

Unbeknownst to her, "Tomura"'s procedure to receive All For One had resulted in a slowly growing fusion between the real Tomura and All For One, as Tomura's resistances start to permeate the outside. Star and Stripe is shocked to see "Tomura" move despite her declaration, wondering if this means he "isn't Tomura Shigaraki", as an explosion suddenly goes off.

With her Quirk and the lasers having been ineffective, Star and Stripe realizes that Tomura had graduated from being a threat to Japan to being a threat to the entire world and tells her team to call Commander Agpar so she can exercise her special authority.

While waiting for Agpar to send in their trump card, Star and Stripe uses her Quirk to shape the air into the form of her body, but much larger. Making the giant air effigy mimic her movements, she uses Fist Bump to the Earth to send various strikes at "Tomura" and then orders her team to aim their lasers at her. She uses her Quirk to combine the lasers into a giant energy sword for her giant air construct to wield. The giant air clone utilizes Keraunos to take the laser blade and stab "Tomura" down into the ocean below, though it’s not nearly enough to finish him.

While keeping the villain pinned, Star and Stripe receives a call from Agpar, reprimanding her for her impulsiveness. He tells her the time has come for her to surpass All Might and to make good use of the special missiles he sent her.

The missiles, known as Tiamat, arrive at the battlefield, as Star and Stripe is forced to disabled the laser sword rule so that she can set a rule on the missiles. The team uses their lasers to keep "Tomura" pinned in the meantime. After grabbing the missiles with her giant air self, she has them swing around and punch Tomura with the missiles in her air effigy's fist, resulting in a powerful explosion known as the State-of-the-Art Hypersonic Intercontinental Cruise Punch, that could be seen all the way from the mainland.

"Tomura" was able to escape most of the danger, however, by using Decay to rot away a hole in the ocean floor where he could hide. After the explosion, "Tomura" leaps up onto one of the jets. The pilot tells Star and Stripe to attack with the giant air double, believing that the explosion from the plane would be enough to kill "Tomura", but she hesitates to kill her friend. This allows Tomura the chance to jump at her and grab her face.