Hearthstone's Kobolds and Catacombs Expansion Detailed

Blizzard has revealed more details about Hearthstone's newest expansion that arrives next month.
Called Kobolds and Catacombs, the expansion was announced earlier today at Blizzcon. A new Hearthstone panel focusing on the update brought additional information, starting with the unveiling of 14 cards seen in the gallery below.
All nine playable classes will get a new upgradeable spell they can slot into their deck, called a Spellstone, providing more unique flavor for each class. Each Spells