From the publisher's blog:

This will be our first two Specialist packs: a Dwarven Battalion and a Goblin Skirmishers set. These packs introduce new units to the game, along with the Specialist and Weapon summary cards necessary to field them. For now, let’s just say that they will significantly alter your game.

The package will include the following:

4 Iron Dwarf Bagpipers
8 Iron Dwarf Spear Bearers
8 Iron Dwarf Axe Swingers
14 new banners
Rules booklet with 2 new adventures
3 new specialist cards and
3 new weapon Summary cards