StarCraft 2 expansion Legacy of the Void was a big part of the opening ceremony at BlizzCon 2014. Blizzard shared the first trailer and details on the end to the SC2 trilogy.
"You are Hierarch Artanis, leader of the mighty protoss race," reads the newly launched website. "Years ago, your homeworld of Aiur fell to the merciless zerg Swarm. Now, at long last, you have raised a powerful fleet of warships known as the Golden Armada, and are poised to reclaim your world. But an ancient evil—Amon—threatens this destiny and the fate of the entire galaxy. Only you can reunite the protoss factions and defeat the coming darkness before it consumes all life in the sector."
The expansion will wrap up the story started with Wings of Liberty and continued by Hearts of the Swarm. We'll finally get to find out what happens to Kerrigan, Raynor and the rest of the gang.
The multiplayer side of Legacy of the Void includes a new co-op experience called Archon Mode. Two players share a base and fight against a pair of enemies.
"By sharing the responsibility of commanding troops and managing resources, players can focus on their own areas of the battle and execute more intricate strategies."
The other new co-op mode in Legacy of the Void is called Allied Commanders. Players become famous characters from StarCraft lore and complete objectives as a team. Every commander has a different set of abilities and strengthens their army in different ways. Players can upgrade their character over time as they complete missions.
Blizzard is also sprucing up the normal competitive multiplayer. Zerg players will be able to build Lurkers, defensive units from StarCraft 1 that burrow underground and ambush any enemies that approach. Terrans can upgrade their Battlecruisers to teleport anywhere on the battlefield. One of the new Protoss units is the Disruptor, an energy weapon used to bombard ground units. Players will be able to organize events more easily thanks to an automated tournament system.
Unlike Heart of the Swarm, Legacy of the Void is a standalone product. You don't need to own Wings of Liberty or Swarm to play it. That could mean Blizzard will charge more for Void but they haven't announced a price yet.