Other features in the expansion includes a 20 mission campaign, new maps and units, and ”expanded functionality.”
According to Blizzard, Kerrigan will play much like the Hero characters that were in Blizzard’s other real-time strategy game, Warcraft III, along with access to high-level spells and abilities as with infinite respawns. Kerrigan will be a part of the new Evolution System in which players can level not only Kerrigan, but regular units as well.
Zerg players will also gain access to the new Viper aerial unit, which owns three unique abilities, and the Swarm Host, ”a slow-moving ground unit that has no standard attack but when burrowed spawns a continuous stream of slow-moving melee units called Locusts that can be used to lay siege and pressure entrenched enemy positions.” However, the Overseer has been removed; the Viper made it superfluous.
Starcraft II: Heart of the Swarm will be released sometime in 2012.
