From Liquipedia Hearthstone Wiki
Double the damage and healing of your spells and Hero Power.
He's been exiled from his home, and all his brothers turned evil, but otherwise he doesn't have a lot to complain about.
|Shadowform||Epic||Priest||Spell||General||3||Your Hero Power becomes 'Deal 2 damage'. If already in Shadowform: 3 damage.|
|Holy Nova||Free||Priest||Spell||General||5||Deal 2 damage to all enemies. Restore 2 health to all friendly characters.|
|Mind Blast||Free||Priest||Spell||General||2||Deal 5 damage to the enemy hero.|