Overwatch's new and 24th hero is the tank Orisa, who fights with a "fusion driver," or a projectile machine gun. In a developer update video, Kaplan says her weapon has more range than nearly any other tank hero. She's currently on the PTR.
Orisa's overview describes her as the "central anchor of her team," who defends with a protective barrier. Her "fortify" ability allows her to reduce incoming damage, and her protective barrier allows her to shield allies, similar to Zarya.
Here's her origin story: