Lurker (StarCraft II)

In the current version of StarCraft II, lurkers only appear in the Galaxy Map Editor, and the Heart of the Swarm campaign.

However, it appears in the Legacy of the Void multiplayer game, with enough range to outrange base defenses. It is a tier 2 unit.

Strategies
In Legacy of the Void, lurkers serve as siege and harassment units, along with being able to defend key locations. They deal splash damage to large numbers of units.

Heart of the Swarm Campaign
The lurker is useable in the campaign as an evolution split from the hydralisk. It deals more damage and has more life than usual. Its counterpart is the impaler. Compared to the impaler, the lurker has lower range, but is more effective against zealots and marines thanks to its splash attacks.

Co-op Missions
The lurker den and lurker strains are exclusive to Kerrigan in Co-op Missions, unlocked once she reaches Level 5.