Starcraft II Heart of the Swarm is a Real-time Strategy and the second installment of Satrcraft II trilogy created by Blizzard Entertainment. The expansion introduces additional units, and also a few changes to multiplayer mode. Heart of the Swarm also continues single player campaign, this time focusing on the Zerg species.
The story of Heart of the Swarm begins two years after the final scenes of Wings of Liberty. It will focus on the Zerg race and feature Sarah Kerrigan as the protagonist. The campaign begins with Kerrigan's quest to assume leadership of the swarm and exact her revenge on Arcturus Mengsk, Emperor of the Terran Dominion. Sarah has to take control of the scattered Zerg, now led by rivaling queens, and lead them to victory. All that while General Warfield of the Dominion is attempting to eradicate the Zerg on Char.
The game features around 20 single player missions and introduces new units for multiplayer mode. Campaign varies from the one in the Wings of Liberty. Kerrigan plays the role of a hero unit (just like in Warcraft III). She is able to respawn after death and use different sets of skills (e.g. Spec Ops and Corruption).
Additionally, Starcraft 2: Heart of the Swarm comes with an arcade which is full of loads of other Starcraft related games, so effectively players get several games in one. The mini games can be searched for by genre and you can provide a rating for the stuff you've played, in order to allow the better efforts to rise to the top!