Hearthstone's last expansion of the year was announced during the opening ceremony at BlizzCon. "Mean Streets of Gadgetzan" takes you through the dark alleys of the largest port town of Azeroth, which executive producer Hamilton Chu described as "the true face of Gadgetzan".

The card packs feature three notorious crime families of Gadgetzan, each with iconic cards that represent the family's identity. Piranha Launcher was announced for crime family Grimy Goons, a card which summons a Piranha each time your Hero attacks. Jade Lotus, an assassin group, introduced the Lotus Assassin card, while Kabal Talonpriest represented his family of mana-hungry spellcasters who boast of their potion-making skills.

The Mean Streets of Gadgetzan cards are available for play at BlizzCon, and more cards will be introduced in the convention's remaining Hearthstone sessions.