If you're into your Warcraft lore, then you more or less already know about Sylvanas Windrunner and her unfortunate death to Arthas. Though resurrected, she came back as Sylvanas, the Queen of the Forsaken, wielding her powerful bow and demonic abilities.
She makes her debut in Heroes of the Storm, bringing along some sweet abilities.
Withering Fire allows you to concentrate your fire on targets ahead, while arrows will shoot at enemies at her backside.
Shadow Dagger will do continuous damage to an enemy or enemies that are clumped together.
Haunting Wave is Sylvanas' escape ability, as it allows her to teleport through enemies or even through walls.
Lastly, her Possession ability will allow her to take control of enemy units for a brief period of time.
You can check out her entire skillset in the video below: