Blizzard revealed Overwatch‘s Zarya will be on the way as a playable character. However not much detail has been revealed about how she will be in-game, but she plays similarly to Rexxar, she is a ranged Warrior.
She will play as she does in any Overwatch game, it appears, with all of the same abilities. These include Particle Grenade (basically her Overwatch weapon’s secondary fire), Personal Barrier (a shield applied to her), and Shield Ally. For her Heroics, you can choose from Graviton Surge (which pulls nearby enemies into a designated spot, as in Overwatch) and Expulsion Zone (a zoning tool that knocks back enemies who enter a certain area).
Zarya is the second Overwatch character (after Tracer, the first) to be integrated into HotS. Tracer was actually added before Overwatch was released.
Zarya also has some alternative skins, including her Master Skin, and one called Thunder Guard Zarya which has some cool themed abilities.
The video showcases some other new skins and another new character, Alarak, who will be a part of a big Starcraft-themed event.