BROODMOTHER OF THE SWARM
If Kerrigan is the Queen of the zerg, then Zagara is the mother of the brood. Cunning and tenacious, she commands her vicious minions on the field of battle. Encounter her brood and beware: mess with her children and you answer to mama.
Zagara can fire a stream of deadly banelings that explode on contact in a shower of acid, melting enemies and structures caught in the splash.
The broodmother doesn't have to always do her own dirty work. She can summon a hydralisk to the field to relentlessly attack any target of her choosing.
Zagara can place a pair of Nydus Worms around the battlefield, which allow her to travel quickly between those two points. This ability greatly extends her mobility and presence across large maps.