24 packs per box.

Twilight of Dragons is the third and final set in the World of Warcraft Worldbreaker block. There are 220 cards in the set (80 common, 55 uncommon, 20 hero, 55 rare, and 10 epic).  

Each booster pack includes 20 cards - 19 game cards and 1 crafting card (loot cards are randomly inserted and replace hero cards).

The set features the Black and Twilight Dragonflights, led by Master Hero Deathwing himself. The stash keyword continues to evolve in this set as well.

The loot cards are:
Common: Landro's Lil' Saber Cub
Uncommon: Fool's Gold
Rare: Amani Dragonhawk Mount

Twilight of the Dragons Mechanics:

The final battle for Azeroth takes center stage as Deathwing and his minions, the Black and Twilight Dragonflights, battle the heroes of the Horde and Alliance. All the themes of Worldbreaker block continue on, including Worgens and Goblins, new race/class combinations, damage types, and specific keywords.

Constant Hero Powers:

Continuing with a theme of the first two sets, Hammer of Twilight will feature continuous hero flip powers. Instead of the heroes of previous years, once flipped, these new heroes influence play for the remainder of the game.

Black and Twilight Dragonkin:

In the final set of the block, the Black and Twilight Dragonkin finally make their presence felt. The Black Dragonkin punish players indiscriminately for their transgressions, while the Twilight Dragonkin compel you to forge a path of destruction before unleashing their full power.

Stash:

The flagship mechanic of the block continues in Twilight of the Dragons. Stash cards reward you when they go into your resource row from anywhere, and you'll find Stash on allies, abilities, and equipment.

Fire Damage:

Rounding out the damage type theme of the block, Twilight of the Dragons focuses on Fire damage. You'll find plenty of allies, ability, and equipment to burn away the opposition, including Deathwing and his minions.