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

Aligned with the five elements, these fast and fierce distant relatives to dragons are summoned  into your armies to battle alongside your troops. Their hardened skin can bolster the defensive capabilities of any army they fight for, provided your opponent doesn't locate their vulnerable side.

For even more choices to add Dragonkin to your armies, look for the Dragon Dice® Eldarim expansion. (sold separately)

Each expansion contains 12 Dragonkin units, 6 small, 3 medium, 2 large and 1 champion, each in a random assortment of five colors and three types.

Use of this expansion requires the Dragon Dice® starter set and Standard rules.  The rules for these dice along with the full standard rules are available from SFR, Inc. at www.sfr-inc.com

NOTE: this product introduces three new Dragonkin Champions. They have the following icons:
Dragonvictor: ID, Belly, SFR logo, Breath, Counter, Rend
Dragonvedette: ID, Belly, SFR logo, Breath, Smite, Fly
DragonStallion: ID, Belly, SFR logo, Breath, Trample, Fly