In StarCraft II, which 2013 expansion follows Sarah Kerrigan’s campaign as the Zerg leader?

The 2013 StarCraft II expansion that follows Sarah Kerrigan’s campaign as Zerg leader is Heart of the Swarm.

Heart of the Swarm is the second major installment in the StarCraft II trilogy. Its story begins after Wings of Liberty and centers on Kerrigan’s transformation, her search for power, and her struggle against enemies including Arcturus Mengsk.

The campaign uses a Zerg-focused progression system. Kerrigan can develop new abilities, while individual Zerg strains can be customized between missions. The story also returns to important locations such as Char and Zerus.

Heart of the Swarm is sometimes confused with Legacy of the Void, the third trilogy installment. Legacy of the Void focuses primarily on the Protoss and Artanis, whereas Heart of the Swarm is built around Kerrigan and the Zerg.