This is the dragonkin expansion. Text on the back of the box:

The mysterious Eldarim have begun to teach their singular elemental skills to a few chosen Acolytes, who have abandoned their racial traditions to become a new race in Esfah. Your battles will be enhanced by using the powerful Dragonmasters and Dragonhunters, the single-element Acolytes of the Eldarim, and the protective Dragonkin whose elemental nature links them with the Eldarim.

Eldarim Expansion: Dragonkin; Box contains 6 common dragonkin, 3 uncommon dragonkin, 2 rare dragonkin, and 1 dragonkin champion in a random assortment of types and colors.

This is the retail box.