From the announcement:
Fantasy Flight Games is proud to announce three additional Ally Packs and Villain Packs for Imperial Assault:
Wookiee Warriors Ally Pack
Hired Guns Villain Pack
Stormtroopers Villain Pack
Whether you fight for the Galactic Empire, the Rebel Alliance, or the galaxy's mercenaries, reinforcements can bring victory to the most dire situations. Now, you can muster additional squads of Stormtroopers, unleash the fury of an enraged Wookiee, or enlist new forces quickly by purchasing the services of some hired guns.
Each figure pack has plenty to tip the odds in your favor, whether you play a campaign or a skirmish. In each expansion, you’ll find sculpted plastic figures to swell your armies, alongside a new campaign side mission and a new skirmish map with two skirmish missions. Combined with new Deployment cards, Command cards, Reward cards, and Agenda cards, these figure packs expand your options for any game of Imperial Assault. Unlike other Ally Packs and Villain Packs, these figure packs do not replace tokens found in another expansion. Instead, this wave of Ally Packs and Villain Packs offers brand-new units to introduce to your games of Imperial Assault for the first time!