Deckard Cain is the latest big name character making the jump to Heroes of the Storm, with Blizzard announcing the Diablo loremaster with a new trailer and a bio that reveals some interesting abilities for the next healer to enter the Nexus. Here's the official bio, which details Deckard's particular set of skills ahead of his appearance in HotS (first on the PTR, where he'll be arriving "soon").
As an avid scholar, Deckard Cain has dedicated his life to the pursuit of knowledge. He has been an advisor, storyteller, and friend to Sanctuary's greatest heroes, guiding them through peril time and again. When Deckard speaks, it's wise to stay awhile and listen.
Healing Potion - Throw a Healing Potion on the ground that heals the first allied Hero that comes in contact with it for 230. Limit 0 active Potions.
Horadric Cube - Throw the Horadric Cube, dealing 80 damage to all enemies in the area and Slowing them by 40% for 1.75 seconds.
Scroll of Sealing - Unfurl an enchanted scroll, forming a triangle that deals 150 damage to enemies inside and Roots them for 1.5 seconds.
Stay Awhile and Listen - After 1 second, Channel for 3 seconds, putting enemy Heroes in front of Deckard to Sleep while Channeling, and for 2 seconds after. Enemies can only be put to Sleep once per cast, and Sleep's effects end instantly if they take damage.
Lorenado - Vector Targeting Create a swirling lorenado that travels in the targeted direction, continually knocking away enemies that come into contact with it.
While we're on the subject of lore, Blizzard is also readying a comic called Rise of the Raven Lord, which should give fans a chance to delve deeper into the world being built around the all-star lineup found in HotS. More info on that is coming later this month.