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Heavy Defense Warrior
Lurkers must burrow in order to attack, rendering them invisible from enemy attackers.
Lurkers are particularly effective as a defense against enemy raids on workers. As long as the defenders can keep enemy detectors from penetrating, raiders deployed by air transport are at risk of being annihilated by pre-deployed Lurkers that they cannot see. Terrans are not as handicapped against lurkers because of the ComSat station.
The lurker's attack does linear splash damage to allied and enemy ground units, but not the player's other ground units, in its path. The lurker has no means of defending itself when not burrowed, and is vulnerable during the process of burrowing; this takes more time than for other units and enemy units can still attack them at that stage, possibly killing the lurker before it even has a chance to effectively become invisible to the enemy and attack.
Lurkers may burrow even if the ability has not been researched. Lurkers may attack only when burrowed.